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diff --git a/77383-h/77383-h.htm b/77383-h/77383-h.htm new file mode 100644 index 0000000..45203b2 --- /dev/null +++ b/77383-h/77383-h.htm @@ -0,0 +1,2325 @@ +<!DOCTYPE html> +<html lang="en"> +<head> + <meta charset="UTF-8"> + <meta name="viewport" content="width=device-width, initial-scale=1"> + <title> + Photography Self Taught | Project Gutenberg + </title> + <link rel="icon" href="images/cover.jpg" type="image/x-cover"> + <style> + +body { margin-left: 10%; margin-right: 10%; } + +h1,h2,h3,h4,h5,h6 { text-align: center; clear: both; } +.h_subtitle{font-weight: normal; font-size: smaller;} + +p { margin-top: .51em; text-align: justify; text-indent: 1.5em; margin-bottom: .49em; } +p.no-indent { margin-top: .51em; text-align: justify; text-indent: 0em; margin-bottom: .49em;} +p.neg-indent { text-indent: -1.5em; margin-left: 5%; margin-right: 5%; padding-left: 1.5em;} +p.f110 { font-size: 110%; text-align: center; text-indent: 0em; } +p.f120 { font-size: 120%; text-align: center; text-indent: 0em; } +p.f150 { font-size: 150%; text-align: center; text-indent: 0em; } + +.fs_120 { font-size: 120%; } + +.spa1 { margin-top: 1em; } +.spa2 { margin-top: 2em; } + +.spb1 { margin-bottom: 1em; } +.spb2 { margin-bottom: 2em; } + +hr { width: 80%; margin-top: 2em; margin-bottom: 2em; margin-left: 10%; margin-right: 10%; clear: both; } +hr.chap {width: 65%; margin-left: 17.5%; margin-right: 17.5%; margin-top: 2em; margin-bottom: 2em;} + @media print { hr.chap {display: none; visibility: hidden;} } +hr.r10 {width: 10%; margin-top: 0.5em; margin-bottom: 0.5em; margin-left: 45%; margin-right: 45%;} + +div.chapter {page-break-before: always;} +h2.nobreak {page-break-before: avoid;} + +table { margin-left: auto; margin-right: auto; white-space: nowrap; + border-spacing: 0px; border-collapse: collapse; } + +th, td { padding-top: 0px; padding-bottom: 0px; + padding-left: 0px; padding-right: 0px; } + +.tdl {text-align: left;} +.tdr {text-align: right;} +.tdc {text-align: center;} +.tdc_bott {text-align: center; vertical-align: bottom;} +.tdl_top {text-align: left; vertical-align: top;} +.tdl_ws1 {text-align: left; vertical-align: middle; padding-left: 1em;} +.tdl_ws2 {text-align: left; vertical-align: middle; padding-left: 2em;} +.tdl_wsp {text-align: left; vertical-align: middle; padding-left: 0.5em;} +.tdr_wsp {text-align: right; vertical-align: middle; padding-right: 0.5em;} + +.pagenum { + position: absolute; + left: 92%; + font-size: small; + text-align: right; + font-style: normal; + font-weight: normal; + font-variant: normal; + text-indent: 0; +} + +.blockquot { margin-left: 12%; margin-right: 12%; } + +.bb {border-bottom: solid thin;} +.bt {border-top: solid thin;} +.br {border-right: solid thin;} +.bl {border-left: solid thin;} +.bbox {border: solid medium;} + +.center {text-align: center; text-indent: 0em;} + +img { max-width: 100%; height: auto; } + +.figcenter { margin: auto; text-align: center; + page-break-inside: avoid; max-width: 100%; } + +.footnotes {border: 1px dashed;} +.footnote {margin-left: 10%; margin-right: 10%; font-size: 0.9em;} +.footnote .label {position: absolute; right: 84%; text-align: right;} +.fnanchor { + vertical-align: super; + font-size: .8em; + text-decoration: + none; +} + +.transnote {background-color: #E6E6FA; + color: black; + font-size:small; + padding:0.5em; + margin-bottom:5em; + font-family:sans-serif, serif; +} + +.ws3 {display: inline; margin-left: 0em; padding-left: 3em;} + + </style> +</head> +<body> +<div style='text-align:center'>*** START OF THE PROJECT GUTENBERG EBOOK 77383 ***</div> + + +<p><span class="pagenum" id="Page_1">[Pg 1]</span></p> + +<hr class="chap x-ebookmaker-drop"> + +<div class="chapter"> +<p class="f120">LITTLE BLUE BOOK NO. 1139<br> +Edited by E. Haldeman-Julius</p> + + <h1>Photography<br>Self Taught</h1> + + <p class="f150"><b>Lloyd I. Snodgrass</b></p> + + <p class="center">HALDEMAN-JULIUS COMPANY<br>GIRARD, KANSAS</p> + + <p class="center">Copyright, 1926,<br>Haldeman-Julius Company</p> + +<p class="center"><span class="pagenum" id="Page_2">[Pg 2]</span> +PRINTED IN THE UNITED STATES OF AMERICA</p> + +<p><span class="pagenum" id="Page_3">[Pg 3]</span></p> +</div> + +<hr class="chap x-ebookmaker-drop"> +<div class="chapter"> + <p class="f150"><b>CONTENTS</b></p> +</div> + +<table class="spb1"> + <tbody><tr> + <td class="tdr">Chapter</td> + <td class="tdl"> </td> + <td class="tdr">Page</td> + </tr><tr> + <td class="tdr"><b>I.</b></td> + <td class="tdl_wsp"><b>INTRODUCTION</b></td> + <td class="tdr"><a href="#Page_5"> 5</a></td> + </tr><tr> + <td class="tdr"> </td> + <td class="tdl_ws1">Simplicity of Photography—Early Stages.</td> + <td class="tdr"> </td> + </tr><tr> + <td class="tdr"><b>II.</b></td> + <td class="tdl_wsp"><b>MATERIALS OF PHOTOGRAPHY</b></td> + <td class="tdr"><a href="#Page_7"> 7</a></td> + </tr><tr> + <td class="tdr"> </td> + <td class="tdl_ws1">Types of Cameras—Lenses—Stops and Shutters—</td> + <td class="tdr"> </td> + </tr><tr> + <td class="tdr"> </td> + <td class="tdl_ws1">Films and Plates—Printing Papers.</td> + <td class="tdr"> </td> + </tr><tr> + <td class="tdr"><b>III.</b></td> + <td class="tdl_wsp"><b>MAKING THE PICTURE</b></td> + <td class="tdr"><a href="#Page_24">24</a></td> + </tr><tr> + <td class="tdr"> </td> + <td class="tdl_ws1">Loading the Camera—Choice of Subject and Viewpoint</td> + <td class="tdr"> </td> + </tr><tr> + <td class="tdr"> </td> + <td class="tdl_ws1">—Steps in taking the Picture—Making the Exposure—</td> + <td class="tdr"> </td> + </tr><tr> + <td class="tdr"> </td> + <td class="tdl_ws1">Exposure Tables—Home Portraiture.</td> + <td class="tdr"> </td> + </tr><tr> + <td class="tdr"><b>IV.</b></td> + <td class="tdl_wsp"><b>DEVELOPING THE NEGATIVE</b></td> + <td class="tdr"><a href="#Page_38">38</a></td> + </tr><tr> + <td class="tdr"> </td> + <td class="tdl_ws1">Chemical Process—Tank Development—Tray Development</td> + <td class="tdr"> </td> + </tr><tr> + <td class="tdr"> </td> + <td class="tdl_ws1">—Negative Defects.</td> + <td class="tdr"> </td> + </tr><tr> + <td class="tdr"><b>V.</b></td> + <td class="tdl_wsp"><b>PRINTING THE PICTURE</b></td> + <td class="tdr"><a href="#Page_46">46</a></td> + </tr><tr> + <td class="tdr"> </td> + <td class="tdl_ws1">Printing Papers—Printing Process—Enlarging—Toning</td> + <td class="tdr"> </td> + </tr><tr> + <td class="tdr"> </td> + <td class="tdl_ws1">—Finishing the Picture.</td> + <td class="tdr"> </td> + </tr><tr> + <td class="tdr"><b>VI.</b></td> + <td class="tdl_wsp"><b>MOTION PICTURES</b></td> + <td class="tdr"><a href="#Page_56">56</a></td> + </tr><tr> + <td class="tdr"> </td> + <td class="tdl_wsp">Importance—Principle—Pictures in the Home—Ciné-Kodak</td> + <td class="tdr"> </td> + </tr><tr> + <td class="tdr"> </td> + <td class="tdl_ws1">—Film Libraries.</td> + <td class="tdr"> </td> + </tr><tr> + <td class="tdr"><b>VII.</b></td> + <td class="tdl_wsp"><b>SCOPE OF PHOTOGRAPHY</b></td> + <td class="tdr"><a href="#Page_61">61</a></td> + </tr><tr> + <td class="tdr"></td> + <td class="tdl_ws1">Business—Scientific Investigation—Illustrations—</td> + <td class="tdr"></td> + </tr><tr> + <td class="tdr"></td> + <td class="tdl_ws1">Color Photography—Color Printing Processes</td> + <td class="tdr"></td> + </tr><tr> + <td class="tdr"></td> + <td class="tdl_ws1">—Other Advances.</td> + <td class="tdr"></td> + </tr> + </tbody> +</table> + +<p><span class="pagenum"><a id="Page_4"></a>[Pg 4]</span></p> +<hr class="chap x-ebookmaker-drop"> +<div class="chapter"> + +<p><span class="pagenum"><a id="Page_5"></a>[Pg 5]</span></p> + + <p class="f150"><b>PHOTOGRAPHY SELF TAUGHT</b></p> + +<hr class="chap x-ebookmaker-drop"> + + <h2 class="nobreak">CHAPTER I<br> +<span class="h_subtitle">INTRODUCTION</span></h2> +</div> + + +<p>Of all the fields of applied science, there is perhaps no other that +has such a universal appeal as photography. While a science in the true +sense of the word it enters so intimately and frequently into contact +with our daily lives that we hardly realize its scientific aspect.</p> + +<p>Photography is simply the making of permanent images of natural +objects on suitably prepared surfaces by physical and chemical means. +The process is easily understood and the actual making of good +pictures is simplicity itself. The light reflected from the subject +being photographed passes through the lens and forms an image on the +sensitive material at the back of the camera. An exposure of only a +small fraction of a second, if the light is good, affects this material +but not to the extent of forming a visible image. The actual image is +brought out later by a chemical process called “development.” After +being “fixed” so the image won’t fade, the “negative,” as the film +or plate is now called, is washed and dried and is then ready for +printing. This is done by allowing a given amount of light to pass +through the negative onto a piece of sensitive paper with which it is +placed in contact. After being developed, washed and dried, this paper +is the finished print or picture. +<span class="pagenum" id="Page_6">[Pg 6]</span></p> + +<p>Photography had its early beginning back in the fore part of the 18th +century⁠<a id="FNanchor_1_1" href="#Footnote_1_1" class="fnanchor">[1]</a> +when the “Camera Obscura” was devised.</p> + +<p>This was a box equipped with a lens at one end and a piece of ground +glass at the other, used by artists to trace a picture on the glass. +Some time later various experiments were made to find something to +replace the ground glass which would permanently retain the image. +Eventually it was discovered that silver chloride would darken upon +exposure to light and that <i>hypo</i> would remove the unexposed +chemical, thus fixing the image more or less permanently.</p> + +<p>Later came the daguerreotype and the wet plate process. The latter +was very cumbersome, but many beautiful pictures were made by it, as +witnessed by Brady’s collection of Civil War pictures. These were +succeeded by dry plates which in turn have quite largely given way to +films.</p> + +<p>Photography as it exists today covers a very broad field, and many +books have been written on the subject as a whole and its various +phases. In compiling the material for this Little Blue Book, an +attempt has been made to include only those topics which will be +of interest and assistance to the average amateur photographer. +Scientific processes are explained in such a way that the beginner, +with no previous experience in the making of pictures, should be able +to understand the various steps as they are taken up, and to get good +pictures. The last chapter is devoted to the scope of photography, its +practical applications, and to some of the developments that are now +taking place.</p> + +<hr class="chap x-ebookmaker-drop"> + +<div class="chapter"> +<p><span class="pagenum" id="Page_7">[Pg 7]</span></p> + <h2 class="nobreak">CHAPTER II<br> +<span class="h_subtitle">MATERIALS OF PHOTOGRAPHY</span></h2> +</div> + +<p>He who builds a house, manufactures an automobile, works the farm, +or produces a picture, must have certain materials and tools to work +with. In the case of photography the tools consist of the camera and +its accessories, the sensitive films or plates, chemicals and other +supplies.</p> + +<h3>TYPES OF CAMERAS</h3> + +<p><i>Box Cameras</i>, when reduced to their simplest form, consist of a +light tight box with a lens at one end and a place for the sensitive +film at the other. Such cameras are usually fitted with a fixed focus +single (meniscus acromatic) lens, one or two ground glass view finders, +and a simple type of shutter. Also, there may be a system of two or +three “stops” for regulating the amount of light admitted by the lens.</p> + +<p>A camera of this type is well suited for children and for the beginner. +There is nothing much to get out of order, the camera is ready on the +instant for whatever photographic subject may turn up, and the pictures +obtained compare very favorably with those produced by the most +expensive instruments. However, such cameras have their limitations. +Snapshot exposures are only possible in good light when the sun is +shining on the subject; objects nearer than about 10 feet cannot be +<span class="pagenum" id="Page_8">[Pg 8]</span> +photographed unless an auxiliary lens is used over the regular lens, +and the camera is not so convenient for carrying as a folding type. The +Brownie is one of the best known of box cameras.</p> + +<p><i>Folding cameras</i>, such as the Kodaks, are preferred by the great +majority of workers. These range from the very small folding models of +vest pocket size taking pictures 1⅝ × 2½ inches, through the 2¼ × 3¼, +2½ × 4½, 2⅞ × 4⅞, up to the 3¼ × 5½, which is one of the most popular +sizes.</p> + +<p>Cameras of this type ordinarily have rapid lenses and many are fitted +with the highest type of anastigmat lenses. Brilliant view finders +are usually furnished as the image is much more clearly seen than in +a ground glass finder. They are ordinarily fitted with shutters which +in addition to time and bulb action may work at automatic speeds from +one second to perhaps ¹/₂₀₀. This makes it possible to get snapshots +of subjects under conditions that would be out of the question with +the box cameras with their slower lenses and shutters. Some of these +cameras are provided with an autographic feature so that data can be +made on the film at the time of the exposure. Some are fitted with +combination backs so that accurate focusing may be done on the ground +glass on the back. Most styles use roll film although some are fitted +to take film packs and cut film.</p> + +<p><i>Reflecting cameras</i> fitted with focal plane shutter, are the type +preferred by many advanced workers. A mirror reflects the image onto +a ground glass, full size and right side up where it is focused and +remains visible in a hood until the very instant of exposure, and thus +<span class="pagenum" id="Page_9">[Pg 9]</span> +it takes all the guesswork out of composition, lighting and focusing. +Some focal plane shutters work as slow as ⅕ second. Such an exposure +is very useful for home portraits indoors where the light is good. +Focal plane shutters also permit of extremely rapid exposures. Cameras +of this type are used when photographing automobile races, athletic +events, etc. Naturally a reflecting camera is somewhat larger and +heavier than an ordinary folding camera.</p> + +<p>There are also many scientific, commercial and special purpose +cameras, among which might be mentioned stereoscopic, telephoto, +photomicrographic, enlarging, copying and reducing, lantern slide, +identification, finger print, cirkut, panoramic, studio, view and +motion picture cameras.</p> + +<p>Practically all amateur work today is made with small film cameras. +In many of the amateur photographic exhibitions large pictures will +be seen but in most cases the foundation of these pictures was a +small film negative. In selecting a camera it is well worth while to +consider the fact that any camera, even the cheapest will make fair +pictures under favorable conditions. It is only when convenience in +regard to compactness and ease of operation along with the ability to +fully expose and make microscopically sharp pictures under unfavorable +conditions are desired, that the more complicated and expensive models +are of superior advantage.</p> + +<h3>LENSES⁠<a id="FNanchor_2_2" href="#Footnote_2_2" class="fnanchor">[2]</a></h3> + +<p>In order properly to understand the purpose and use of the lens it is +<span class="pagenum" id="Page_10">[Pg 10]</span>necessary to know something about the nature of light. Light ordinarily +travels in a straight line but when a beam falls on a polished surface +such as a looking glass it is reflected back in the same way that a +rubber ball striking the ground rebounds. It is this <i>reflected +light</i> from objects, that reaching our eyes enables us to see them, +and reaching the lens of the camera enables us to photograph them.</p> + +<p>As in the case of sound where low pitched notes are caused by a small +number of vibrations per second and high pitched ones by a great number +so in the case of light the red is produced by long wave lengths and +violet by short ones. Between these are all the other colors from red +to violet—orange, yellow, green, blue. There are wave lengths shorter +than violet called ultra-violet, which are not visible but are very +active in affecting a photographic emulsion. White light is made up by +all colors.</p> + +<p><i>Refraction</i> is another property of light which very directly +concerns our discussion of lenses. When a stick is placed in water at +an angle, it appears to be bent at the surface. The explanation of this +is that in a dense medium, light travels slower than in air. When the +beams strike the surface one part reaches the surface and is slowed up +while the other part is still in the air and traveling faster, thus +causing a change in direction. The same thing taking place in glass +explains the action of light in passing through the lens.</p> + +<p>PINHOLE LENS. The simplest lens which we could use would be a +small hole. If we take a sheet of cardboard and make a hole in it with +a pin and then in a darkened room, hold the cardboard between a sheet +of white paper and an electric lamp we shall see on the paper an image +<span class="pagenum" id="Page_11">[Pg 11]</span> +of the lamp’s filament. The same principle is applied to the making of +pinhole photographs. A very fine smooth hole is made in a piece of thin +brass or tin-foil and this is used in place of the lens. The diagram +(<a href="#FIG_1">Figure 1</a>) shows how the image is formed by the +use of the pinhole.</p> + +<div class="figcenter"> + <img id="FIG_1" src="images/figure_1.jpg" alt="" width="600" height="361" > + <p class="f120"><b>Fig. 1</b></p> +</div> + +<p>Remarkably good pictures can be made with nothing but a pinhole for a +lens. No object is perfectly sharp but all are equally sharp and the +result may be very fine pictorially. However, the exposure is very +long, taking from a few seconds up to several minutes with the object +in good bright sunlight even when a very fast film is being used. As +the pinhole is made larger so as to admit more light, then the image +will become more and more indistinct until no picture is formed at all.</p> + +<p>FORMATION OF AN IMAGE BY A LENS. When a ray of light passes +through a prism it is bent as it enters the glass and again as it +leaves it. The lens works very much the same as two prisms. +<span class="pagenum" id="Page_12">[Pg 12]</span></p> + +<div class="figcenter"> + <img src="images/figure_2.jpg" alt="" width="600" height="226" > + <p class="f120"><b>Fig. 2</b></p> +</div> + +<p>The lens is used in the front of the camera for the purpose of so +directing the rays of light that they will form an image of the object +being photographed on the sensitive film or plate in the back of the +camera. <a href="#FIG_3">Figure 3</a> shows how the image is formed by +the lens. It will be noticed that parallel rays of light are bent so as +to go through F (the principal focus) and that rays passing through the +center of the lens do not change in direction. This determines how far +away the image will be from the lens. If the subject being photographed +is 100 feet from the camera, the image will be formed a fraction of an +inch closer to the lens than will be the image of an object only 10 +feet away. This is shown by dotted lines in the diagram.</p> + +<div class="figcenter"> + <img id="FIG_3" src="images/figure_3.jpg" alt="" width="600" height="143" > + <p class="f120"><b>Fig. 3</b></p> +</div> + +<p><i>Focusing</i> is the bringing of the lens to the proper distance from +the film so that the image will be sharp, and as explained this is +<span class="pagenum" id="Page_13">[Pg 13]</span> +changed according to how far away the object is which is being +photographed. This distance from the optical center of the lens to the +focal plane or position of the films when focused on a distant object +is termed <i>focal length</i>. When choosing a camera and lens for +ordinary usage it is well to select one having a lens of a focal length +at least equal to the diagonal of the negative. A short focal length +lens gives a small image. For this reason the worker is inclined to +approach close to the subject in order to get a larger image. In such +a case any portion of the subject such as a foot or hand of the person +projecting a little toward the camera, will appear much too large in +proportion to the remainder of the subject. This is often noticeable in +amateur pictures. For instance, the focal length of a lens on a post +card size camera should be from 6½ to 7 inches.</p> + +<p>KINDS OF LENSES. The <i>meniscus lens</i> is the simplest +type, being made from a single piece of glass. Such lenses are used +only on small fixed focus cameras. When a beam of light is passed +through a prism it will be noticed that a band of color is formed. This +is because the longer wave lengths such as the red colors are bent less +than the shorter ones such as the violet. A meniscus lens will not +focus the various colors in the same plane and therefore is used only +on the very cheapest cameras.</p> + +<p>A <i>meniscus achromatic</i> lens is more fully corrected, being made +from two kinds of glass, flint and crown, and overcomes the difficulty +just mentioned. Such lenses are used on most of the box cameras and the +<span class="pagenum" id="Page_14">[Pg 14]</span> +less expensive folding models. These lenses are made to be used only +with rather small openings and so the user is limited to making a +snapshot exposure in good bright sunlight. A lens such as this is very +fine for landscape work or portraiture but if the subject is a building +or other object containing straight lines, the lines will appear +slightly curved if they come near the edge of the picture. If the stop +opening is in front of the lens the lines will curve outward, but if +behind it then they will curve inward.</p> + +<p>Double lenses overcome this defect by combining two single lenses, one +in front and one in back of the stop, so as to get straight lines to +photograph as such, clear to the very edge of the picture. These lenses +can be used at much larger stop openings in proportion to focal length +than the meniscus achromatic or single lenses, and hence the name for +the old type of double lens—“rapid rectilinear.” These older double +lenses still have one defect known as astigmatism or the inability to +photograph both vertical and horizontal lines sharply to the very edge +of the picture.</p> + +<p>About 30 years ago, Professor Abbe and Otto Schott working together +at Jena, found how to produce new kinds of optical glass from which +lenses could be made that would give flat field images with the blue +and yellow rays at the same focus. By the use of these new glasses the +opticians have been able to make lenses that give sharp images and a +flat field to the very edge of the picture. These lenses are called +<i>anastigmat</i>. Better defining power, however, can only be obtained +by the most careful and skilled work when making the lens, this work +being of a far higher quality than that applied on the older types of +<span class="pagenum" id="Page_15">[Pg 15]</span> +lenses, which accounts for the higher cost of anastigmats. They can +be used with larger stop openings and thus it is possible to make +snapshots on days when the sun is not shining and also to get slow +snapshot exposures near a window if the light is good.</p> + +<p>The “<i>Kodar</i>” lens is a recent development intermediate in type +between the old “rapid rectilinear” and the anastigmat. It has many of +the practical advantages of the latter though it is an inexpensive type +of lens.</p> + +<p>There are several types of lenses which are used for special purposes. +Two of the most common are wide angle lenses and telephoto lenses. +<i>Wide angle lenses</i> have a very short focal length for the size of +the film or plate covered and are especially useful for photographing +in confined positions, such as in a room where it is desired to include +the greater portion of it. They are also rather necessary when trying +to photograph buildings on the opposite side of a rather narrow street. +The perspective is rather poor when working up close, as nearby objects +appear too large in proportion to those more distant. The room looks +much larger than it really is. Wide angle lenses must always be used +with a smaller stop opening than those of ordinary focal length. For +example, the Bausch & Lomb Medium Wide Angle Protar Lens Series IV has +a maximum speed of f.12.5. The extreme wide angle Protar lens made by +the same firm has its largest stop opening at f.18. The Goerz Hypergon +lens has only a maximum opening of f.22, but this lens embraces an +extremely wide angle of 135 degrees. The lens on the average hand +camera includes an angle of perhaps 42 to 49 degrees. +<span class="pagenum" id="Page_16">[Pg 16]</span></p> + +<p><i>Telephoto lenses</i> on the other hand are most useful for +photographing objects that are so far away as to appear too small with +a normal lens. Not only are they useful for photographing animals, +birds, and other wild life but are useful for taking pictures of +persons or buildings that are not usually accessible. As the light +reflected from the subject must cover a larger proportion of sensitive +film, it naturally follows that the exposure would be longer than when +no telephoto lens was used. A steady tripod must be used as the least +vibration will spoil the picture. A longer bellows draw is generally +necessary although some of the new fixed magnification telephoto lenses +do not require a long bellows extension for the equivalent focal length.</p> + +<p><i>Soft focus lenses</i>, an example of which is the Wollensak Verito +f.4 lens, produce an image which is very pleasing for certain types of +pictorial and portrait work.</p> + +<h3>STOPS AND SHUTTERS</h3> + +<p>When using a camera, it is very necessary to know something about +<i>stops</i> or diaphragm openings.</p> + +<p>A very instructive experiment for the beginner, if he has a camera with +a ground glass focusing screen, is to set it up in front of some well +illuminated object and focus it on the ground glass screen by moving +the lens nearer or further from the ground glass. A coat or other dark +cloth should be thrown over the head of the operator and back of the +camera to exclude the light. When the shutter is set so as to remain +open and the largest stop opening is used it will be noticed that there +is a brilliant image of the subject on the ground glass but that it is +<span class="pagenum" id="Page_17">[Pg 17]</span> +upside down. If the picture being examined is a landscape or other +subject containing objects at different distances, it will also be +noticed that those at a certain distance away will be sharply defined +whereas others nearer and further away are somewhat diffused or +blurred. In other words, they are out of focus.</p> + +<p>If the size of the stop opening in front of the lens is decreased, it +will be noticed that the image of objects nearer and farther than the +one focused on becomes sharper, and that the image is not as bright as +before. Thus we see that the two principal functions of the stop are to +increase or decrease the depth of focus and to regulate the amount of +light admitted to the sensitive film. This last function makes it an +important factor in exposure. In the case of portraits it is usually +better to have only the subject sharp for if the background were also +sharp it would detract from the interest of the subject. For landscapes +it is more necessary to have the entire picture sharp.</p> + +<p>The amount of light reaching a given portion of the sensitive film +depends not only on the size of the stop opening but on the distance of +the lens from the film. With longer focal length lenses the distance +is greater and therefore the light spreads over a larger area. Thus it +is less concentrated, and so the exposure needs to be longer with the +same actual size stop opening. The diaphragm or stop opening is always +referred to in terms of its proportion to the focal length. In one +system the stop is expressed simply as a fraction of the focal length. +Thus, f.8 means that the diameter of the aperture or opening is ⅛ of +the focal length. For example, if the lens opening or stop is ½ inch +in diameter and the focal length is four inches, then the stop is f.8. +<span class="pagenum" id="Page_18">[Pg 18]</span> +Again, if the focal length is 8 inches and the stop opening is one inch +the ratio would be the same, and the stop would be marked f.8. In the +latter case four times as much light would have been admitted, yet it +would have had to cover four times as much space thus giving equivalent +illumination to the film. The comparative exposure of two stops varies +with the square of their f. values, the larger numbered one being the +slower and requiring the longer exposure. In the U. S. (Universal +System), the stops are so marked that each succeeding smaller one +requires twice the exposure of the next larger.</p> + +<p>The following table gives a comparison of the two systems:</p> + +<table class="spb1"> + <tbody><tr> + <td class="tdr_wsp bl bb bt">F.</td> + <td class="tdc bl bb bt"> f.4 </td> + <td class="tdc bl bb bt"> f.5.6 </td> + <td class="tdc bl bb bt"> f.6.3 </td> + <td class="tdc bl bb bt"> f.8 </td> + <td class="tdc bl bb bt"> f.11 </td> + <td class="tdc bl bb bt"> f.16 </td> + <td class="tdc bl bb bt"> f.22 </td> + <td class="tdc bl bb bt"> f.32 </td> + <td class="tdc bl br bb bt"> f.45 </td> + </tr><tr class="bb"> + <td class="tdr_wsp bl bb"> U.S.</td> + <td class="tdc bl bb">1</td> + <td class="tdc bl bb">2</td> + <td class="tdc bl bb">(2½)</td> + <td class="tdc bl bb">4</td> + <td class="tdc bl bb">8</td> + <td class="tdc bl bb">16</td> + <td class="tdc bl bb">32</td> + <td class="tdc bl bb">64</td> + <td class="tdc bl br bb">128</td> + </tr> + </tbody> +</table> + +<p>Most of the rapid rectilinear lenses have U. S. numbers. Anastigmat +lenses usually have f. markings. The single lenses are more often +marked with three or four numbers, 1, 2, 3 and 4, of which each +succeeding larger numbered stop usually admits about half as much light +as the next smaller and therefore requires approximately twice the +exposure.</p> + +<p>The <i>shutter</i> is a mechanical device for controlling the length +of the exposure. One of the simplest forms is shown in the following +diagram: +<span class="pagenum" id="Page_19">[Pg 19]</span></p> + +<div class="figcenter"> + <img src="images/figure_4.jpg" alt="" width="450" height="434" > + <p class="f120"><b>Fig. 4</b></p> + <p class="center spb2"><b>Fig. 4 shows the position of slide B<br> when the smallest + stop is in front of the lens.</b></p> +</div> + +<p>This form is known as a rotary shutter and may give snapshot exposures +of approximately ¹/₂₅ of a second. An instantaneous exposure is made +by pushing lever “C” across in one direction only. Ordinarily the +largest of the three stop openings (controlled by slide “B”) is used +for snapshots in good light, the middle one for snapshot exposures of +very distant objects and for time exposures of interiors. The small one +is more often used for time exposures outdoors. To make a time exposure +slide “A” is pulled up and then when lever “C” is pushed across in one +direction the shutter will open and remain open until lever “C” is +pushed across in the opposite direction. <a href="#FIG_5">Figure 5</a> +<span class="pagenum" id="Page_20">[Pg 20]</span> +illustrates one of the more comprehensive types of shutters. The size +of the stop opening is controlled by moving “B” to the proper f. value.</p> + +<div class="figcenter"> + <img id="FIG_5" src="images/figure_5.jpg" alt="" width="450" height="405" > + <p class="f120"><b>Fig. 5</b></p> +</div> + +<h3>FILMS AND PLATES</h3> + +<p>Photography begins with the chemical action of light on compounds +of silver, particularly those of chlorine and bromine. This action +is familiar to anyone who has added a solution of silver nitrate to +a sodium chloride solution and watched the resulting precipitate of +silver chloride darken after a short exposure to sunlight. Briefly, +films consist of a base or support of either glass or transparent +cellulose on which is coated an emulsion which holds in suspension +some sensitive silver salts. Silver bromide is the principal sensitive +<span class="pagenum" id="Page_21">[Pg 21]</span> +material in films and plates. This, together with the gelatin which +is added to keep it from settling, makes up the emulsion. The +different degrees of sensitiveness are obtained by varying the amount +and duration of heat to which the emulsions are subjected during +manufacture. Other substances may be added which also affect its +sensitiveness.</p> + +<p>The silver bromide or other compound in the emulsion is so sensitive +to light that an exposure in the camera for but a very small fraction +of a second under good lighting conditions, is sufficient to produce +a developable image. The emulsion is composed of innumerable grains, +perhaps from 10 to 30 billion per square inch, lying several deep. +The number acted on during exposure depends on the intensity of the +light and the duration of its access to the film. The light action is +not visible after exposure but every grain that was at all affected +during exposure can be developed. This is explained later in Chapters +III and IV. It naturally follows that if the sensitive film is exposed +to light at any time other than when the picture is being made, for +even the smallest fraction of a second before being developed, it will +be completely fogged as all of the grains of silver bromide will be +affected and when developed will be completely dark.</p> + +<p>In addition to speed another characteristic of modern films and +plates is <i>latitude</i>. This means that the exposure can be varied +considerably without appreciably affecting the final picture. Thus, +if the least correct exposure was ¹/₁₀₀ sec. this could perhaps be +increased to ¹/₂₅, or four times as much, without affecting the final +result except that the negative would be denser and require a longer +time in printing. +<span class="pagenum" id="Page_22">[Pg 22]</span></p> + +<p>Films or plates with very slow emulsions are more often used for +copying and other work where it is desired to have considerable +contrast and where speed is no object. The most rapid emulsions +are necessary where extremely short exposures under ideal lighting +conditions must be given, as for athletic events, and for slow snapshot +exposures in poor light.</p> + +<p>Ordinary plates and films are sensitive to the shorter wave lengths of +light such as the ultra-violet, the violet and the blue, but little if +any to the yellow and red. For this reason a blue flower or similar +subjects will photograph so as to appear almost white, whereas a yellow +or red one will appear nearly dark as the light reflected will not +affect the film to any extent.</p> + +<p>To counteract this some plates and most films are made somewhat +<i>color sensitive</i> or orthochromatic by the incorporation in the +emulsion of certain dyes which makes it less sensitive to blue light +and more to the yellow-green rays.</p> + +<p>For the exact rendering of reds and other colors, plates and films are +sometimes still more fully corrected and these are termed panchromatic. +While they are sensitive to all colors, yet they are somewhat more +sensitive to the blues than the reds, and therefore a filter is often +used.</p> + +<p>The <i>filter</i>, which may be a piece of colored gelatin between two +pieces of glass, is placed over the lens when photographing certain +colored objects, and its function is to absorb or hold back the blue +rays or certain other ones as desired. This will give time for the +yellows and reds to affect the film and thus a denser deposit of silver +will be obtained which will result in that part of the print being +lighter. As the filter holds back some of the most actinic light, it is +<span class="pagenum" id="Page_23">[Pg 23]</span> +evident that the exposure will have to be longer than when no filter is +used. The length of the exposure will depend upon the type of sensitive +emulsion being used and the kind of filter. A variety of filters can +be obtained which will absorb different colors and thus it is possible +to have any given color photograph lighter or darker if desired. For +full correction so that all colors will photograph to appear relatively +as dark as they should, it has been found that Eastman Commercial +Panchromatic Film and a Wratten K-3 filter will produce the desired +result.⁠<a id="FNanchor_3_3" href="#Footnote_3_3" class="fnanchor">[3]</a></p> + +<h3>PRINTING PAPERS</h3> + +<p>Printing papers are sensitive in the same way as films or plates except +that the emulsion is slower, and is coated on a paper base instead of +glass or cellulose. The more rapid enlarging papers have a slow bromide +emulsion while ordinary contact developing printing papers are usually +silver chloride. The various contrasts and surfaces will be discussed +in the chapter on printing.</p> + +<hr class="chap x-ebookmaker-drop"> + +<div class="chapter"> +<p><span class="pagenum" id="Page_24">[Pg 24]</span></p> + <h2 class="nobreak">CHAPTER III<br> +<span class="h_subtitle">MAKING THE PICTURE</span></h2> +</div> + +<h3><i>Loading the Camera</i></h3> + +<p>Most hand cameras are made to take <i>roll film</i>. This is especially +convenient as a darkroom is not required for loading. Extending the +full length of the strip of film and several inches beyond each end is +a strip of lightproof paper, which in connection with the flanges on +the spool, forms a lightproof cartridge.</p> + +<p>The loading operation is performed entirely by daylight, but a position +should be selected where the light is somewhat subdued. Care must be +taken before beginning the work to see that the shutter is closed. The +empty spool is inserted in the winding end and the full spool is placed +in the recess at the opposite end by pulling out the spool pins and +allowing the film cartridge to drop into place, care being taken that +the top of the spool is at the top of the camera. Otherwise the opaque +red paper would be between the lens and the film. The spool pins are +then pushed back into place in the holes at the end of the spool so +that the spool revolves upon them. The gummed strip that holds the end +of the red paper is next removed and the paper is sufficiently unrolled +to thread into the empty spool. Unless it is kept taut it may slip and +<span class="pagenum" id="Page_25">[Pg 25]</span> +loosen sufficiently to admit light which would fog the film. The back +of the camera is next replaced and the winding key turned until the +figure 1 appears at the little red window.</p> + +<p><i>Film packs</i> contain film similar to roll film but cut to the +various sizes in use. They can be loaded and removed from the camera in +daylight, the darkroom only being necessary when the films are to be +removed from the pack and developed. The film pack consists of 12 flat +cut films packed in a lightproof case and attached singly to strips +of black paper the ends of which project from the top of the pack and +terminate in tabs numbered from 1 to 12. By the use of a film pack +adapter an ordinary plate camera is transformed into a daylight loading +film camera. After the pack is placed in position in the camera, the +tab marked “safety cover,” is pulled out and torn off at the place +marked. The first film is now ready for exposure. After making the +first exposure, tab No. 1 is pulled out and torn off in the same manner +and so on until No. 12 is removed which will draw the last film to the +back of the pack. The films now being protected from light, the pack +can be removed in daylight and another inserted.</p> + +<p><i>Plates</i> must be loaded into plate holders or into the plate +magazine in the dark room illuminated only by a safelight lamp. <i>Cut +films</i> are loaded similarly into film holders, film magazines, and +also into film sheaths which are to be used in plate holders, by the +aid of suitable safelight in the darkroom. +<span class="pagenum" id="Page_26">[Pg 26]</span></p> + +<h3>CHOICE OF SUBJECT AND VIEWPOINT</h3> + +<p>There are of course subjects innumerable which will make pleasing +pictures. Regardless of whether the picture is a landscape or a +portrait, there are several points that should be kept in mind in +regard to artistic composition if the picture is to be pleasing +pictorially as well as good technically.</p> + + +<p>COMPOSITION⁠<a id="FNanchor_4_4" href="#Footnote_4_4" class="fnanchor">[4]</a>. +This may be defined as the bringing of things together in an orderly +and symmetrical arrangement. It is not an exact science that can +be depended upon to produce results mechanically, but its general +principles can be applied in such a way as to aid materially in +avoiding the inartistic.</p> + +<p>The first lesson to be learned is to leave out what is not required. +This is known as <i>selection</i>. By moving the camera to the right +or left, up or down, focusing at different planes, and using different +stop openings, much that is objectionable may be either eliminated or +at least made unobtrusive.</p> + +<p><i>Simplicity</i> is the keynote of artistic work. Over-crowding must +be avoided. Ordinarily the picture should have but one object or group +of principal interest, all others being subordinate and helping support it.</p> + +<p>There should be such a combining of masses, tones and lines as +to produce a pleasing whole. This is known as <i>harmony</i> and +<i>balance</i>. Objects should be so grouped that there will not be too +<span class="pagenum" id="Page_27">[Pg 27]</span> +many shadows or highlights of equal importance. The exact center is +the weakest portion of the picture and so important objects should be +a little to one side and in some cases slightly above or below. The +picture should balance, both vertically and horizontally, a large mass +near the center being balanced by several smaller objects on the other +side or by a smaller one further from the center.</p> + +<p>In the case of landscapes, neither the horizon nor a vertical line +should ever exactly divide the picture into two equal parts. If there +are subjects of importance in the near foreground, the horizon line +should be perhaps 1–3 down from the top as this gives a prominent +foreground; for broad expansive views it should be the same distance +from the bottom in order to direct attention to the sky and more +distant parts of the landscape. A clouded sky should be included if +possible. Clouds are a pictorial asset as they break up the monotony of +the white sky and add greatly to the beauty and attractiveness of the +picture, but they cannot ordinarily be obtained without the use of a +filter. A sky filter is a little attachment which slips over the front +of the lens, and as only the upper portion of the filter is colored +it keeps back the excessive light from the sky without appreciably +affecting the exposure. Thus many clouds will be brought out nicely in +the picture which ordinarily do not show because of overexposure.</p> + +<p>In landscape photography it is not generally advisable to introduce +human figures as in nearly all cases they fail, either in costume or in +<span class="pagenum" id="Page_28">[Pg 28]</span> +pose, to harmonize with the subject. The domestic animals, such as +horses, cows and sheep, can, however, frequently be included with +success. When human figures are introduced they should not look +directly at the camera.</p> + +<p>For pictorial landscape work a diffusion attachment as the Kodak +Pictorial Diffusion Disk may be placed over the regular lens or a soft +focus lens such as the Verito⁠<a id="FNanchor_5_5" href="#Footnote_5_5" class="fnanchor">[5]</a> +may be used.</p> + +<p>LIGHTING. This is of equal importance with the arrangement of +the subject in the picture as it determines the strength and position +of the lights and shadows. It is the variation in these that gives the +picture depth and roundness, making the subject stand out from the +surroundings. The beginner when making exposures in the sunlight should +have the sun behind him, but a little to one side. If the illumination +comes from directly back of the camera, the shadows are more or less +lost, giving a flat appearance. However, contrary to the generally +published advice, some of the most pleasing results may be obtained +with the sun from in front but a little to one side. In such a case it +is necessary to shade the lens from the direct rays of the sun. The +exposure should be increased as there are more deep shadows.</p> + +<h3>STEPS IN TAKING THE PICTURE</h3> + +<p>After the folding camera is loaded, there are still the following steps +to be carried out in taking the picture: +<span class="pagenum" id="Page_29">[Pg 29]</span></p> + +<div class="blockquot"> + <p class="neg-indent">1. See that an unexposed portion of film is + in position for the exposure.</p> + + <p class="neg-indent">2. Open the camera, and set the focus if + a focusing model is being used.</p> + + <p class="neg-indent">3. Adjust the diaphragm opening.</p> + + <p class="neg-indent">4. Set the shutter (on some types).</p> + + <p class="neg-indent">5. Hold the camera level and include the + view wanted.</p> + + <p class="neg-indent">6. Make the exposure.</p> +</div> + +<p>1. When roll film is being used, a fresh section should be turned into +position immediately after each exposure. Similarly with film packs the +tab should be pulled out as soon as each exposure is made so as to be +all ready for the next. This is often overlooked by beginners with the +result that two pictures are made on the same section of film.</p> + +<p>2. On the bed of most adjustable hand cameras, is a <i>scale</i> +marked with figures, usually 6 to 100, indicating feet. The front +of the camera must be extended until the pointer is over the figure +indicating the number of feet which the operator has estimated to be +the distance to the subject. Some types of cameras are equipped with a +screw focusing device—a revolving ring, which is marked with a scale +and moves the lens back and forth. When using a large stop and working +up close, it is necessary to estimate the distance carefully but when +using a medium small stop such as f.16 and photographing an object 50 +feet or farther away, the focus need be estimated only with approximate +accuracy.</p> + +<p>If the camera is 3¼ × 4¼ or smaller it may be used as if it were a +<span class="pagenum" id="Page_30">[Pg 30]</span> +fixed focus type by extending the front to the 25 foot mark on the +focusing scale and using stop f.11 (U.S.8).</p> + +<p>3. In choosing the stop to use it is necessary to consider the amount +of light available, the rapidity of movement of the subject, the depth +of focus needed, and the shutter speed that is to be used. Large stops +are necessarily used for slow snapshot exposures under poor lighting +conditions, and for very rapid instantaneous exposures of moving +objects in bright sunlight. They are also used to limit the depth of +focus so as to make the principal object stand out from its background. +This is more particularly desirable in portraiture. Smaller stops +give sharper images especially over a greater depth of field, and are +generally used for groups, views and other subjects, where the entire +picture must be sharp. In such a case it may be necessary to use a +tripod and give a time exposure.</p> + +<p>While there are exceptions to the appended table of stops to be used, +yet it will be helpful, especially to beginners.</p> + +<div class="blockquot"> +<p class="neg-indent">f.4.5 (a) For extra rapid exposures when thelight +is very good, i. e. for moving objects at 1–100 to 1–1000 of a second.<br> +(b) For portraiture indoors when the light is only fair and short time +or bulb exposures are made.<br> (c) For slow snapshots outdoors when +the light is poor, or indoors by a sunlit window. This opening gives +but little depth of focus so the camera must be carefully focused.</p> + +<p class="neg-indent">f.6.3 (a) For quick exposures of moving objects in good +light with shutter speeds to about 1–300 second.<br> +(b) For slower speeds on hazy and slightly cloudy days.<br> +(c) For indoor home portraiture.</p> + +<p class="neg-indent">f.7.7 or f.8 (U.S.4) (a) For instantaneous exposures in +slightly cloudy weather, speed 1–25. (Do not attempt instantaneous +exposures on dark, cloudy days.) +<span class="pagenum" id="Page_31">[Pg 31]</span><br> +(b) For flashlight groups.<br> +(c) For portraiture indoors or outdoors in the shade.</p> + +<p class="neg-indent">f.11 (U.S.8) (a) For all ordinary instantaneous exposures + when the subject is in bright sunshine, using 1–25 sec. <br> +(b) For flashlight interiors.</p> + +<p class="neg-indent">f.16 (U.S.16) (a) For instantaneous exposures when the +sunlight on the subject is unusually strong and there +are no heavy shadows, as for views on the seashore, +or on the water, using speed 1–50.<br> +(b) For ordinary landscapes in bright sunshine with clear +sky overhead, speed 1–25. <br> +(c) For interior time exposures.</p> + +<p class="neg-indent">f.22 (U.S.32) (a) For instantaneous exposures of + extremely distant views.<br> +(b) For marine or snow scenes, or clouds in bright + sunshine, at speed 1–25.<br> +(c) For time exposures of interiors, and of outdoor + scenes in cloudy weather.</p> + + +<p class="neg-indent">f.32, f.45 (U.S.64, U.S.128) (a) For time exposures +outdoors in cloudy weather. Never used for snapshots.</p> +</div> + +<p>4. When making instantaneous exposures it is necessary to see that +the shutter is set at “I.” In addition to this some shutters must be +“set” by special levers, much as a gun is cocked, before they can be +operated. If instantaneous exposures are to be made while holding the +camera, a large enough stop must be used so that the exposure will +be ¹/₂₅ second or less, as few people can hold a camera steady for a +longer time.</p> + +<p>5. When making the exposures, care must be taken to hold the camera +level and have it include the exact view wanted. If the camera is +inclined to one side, horizontal lines will be at an angle in the +<span class="pagenum" id="Page_32">[Pg 32]</span> +picture; if pointed up, a building will photograph smaller at the top; +if down, the opposite will be the case. If the camera is fitted with +a rising front, it will be found useful for eliminating undesirable +foreground or including the top of a tall building. In the case of +architectural subjects it is especially important that the back of the +camera remains vertical in order to prevent any distortion of the lines +of the building.</p> + +<p>A single reversible view finder is provided with most cameras. It is +notched to indicate the view that will be included both when the camera +is used vertically and horizontally. One should always look at the +finder from directly above and not at an angle, or the view included +will not be accurately seen.</p> + +<p>6. Exposure is made by means of a lever, or cable release.</p> + +<h3>MAKING THE EXPOSURE</h3> + +<p>Exposure depends on such a variety of factors that only with practice +will the worker be able to give consistently the correct amount under +varied conditions. Nearly all of the subjects ordinarily photographed +by daylight may be classified into four groups. Since the normal +exposure for each of these groups may be easily memorized, the outdoor +exposure problem is reduced to the simple one of determining to which +group the subject belongs. While the table is eminently satisfactory +for stationary objects, it is not adapted for rapidly moving objects as +the shutter speed would be too slow. When using these tables, a faster +or slower shutter speed may be used if the stop opening is varied +accordingly so as to give the same amount of light. As explained, each +<span class="pagenum" id="Page_33">[Pg 33]</span> +succeeding smaller stop than f.8 (U.S. 4) admits about half as much +light as the next larger. The exposure tables are for from 2½ hours +after sunrise until 2½ hours before sunset on days when the sun is +shining on the subject.</p> + +<p class="f110 spa2"><b>OUTDOOR EXPOSURE TABLES</b><br> +(Rectilinear and Anastigmat Lenses)</p> + +<table class="spb1"> + <thead><tr class="bt bb"> + <th class="tdc_bott" colspan="2">Groups</th> + <th class="tdc_bott"> Shutter <br>Speed</th> + <th class="tdc"> Rectilinear <br>Lenses<br>Stop</th> + <th class="tdc"> Anastigmat <br>Lenses<br>Stop</th> + </tr></thead> + <tbody><tr> + <td class="tdl_top bb" rowspan="3">1—</td> + <td class="tdl">Snow, marine and beach</td> + <td class="tdc_bott bb" rowspan="3">¹/₂₅</td> + <td class="tdc_bott bb" rowspan="3">U.S. 32</td> + <td class="tdc_bott bb" rowspan="3">f.22</td> + </tr><tr> + <td class="tdl">scenes, extremely</td> + </tr><tr> + <td class="tdl bb">distant landscapes</td> + </tr><tr> + <td class="tdl_top bb" rowspan="4">2—</td> + <td class="tdl">Ordinary landscapes</td> + <td class="tdc_bott bb" rowspan="4">¹/₂₅</td> + <td class="tdc_bott bb" rowspan="4">U.S. 16</td> + <td class="tdc_bott bb" rowspan="4">f.16</td> + </tr><tr> + <td class="tdl">showing sky, with a</td> + </tr><tr> + <td class="tdl">principal object in the</td> + </tr><tr> + <td class="tdl bb"></td> + </tr><tr> + <td class="tdl_top bb" rowspan="4">3—</td> + <td class="tdl">Nearby landscapes</td> + <td class="tdc_bott bb" rowspan="4">¹/₂₅</td> + <td class="tdc_bott bb" rowspan="4">U.S. 8</td> + <td class="tdc_bott bb" rowspan="4">f.11</td> + </tr><tr> + <td class="tdl">showing little or no</td> + </tr><tr> + <td class="tdl">sky, groups, street</td> + </tr><tr> + <td class="tdl bb">scenes</td> + </tr><tr> + <td class="tdl_top bb" rowspan="4">4—</td> + <td class="tdl">Portraits in the open</td> + <td class="tdc_bott bb" rowspan="4">¹/₂₅</td> + <td class="tdc_bott bb" rowspan="4">U.S. 4</td> + <td class="tdc_bott bb" rowspan="4">f.7.7 or<br>f.8</td> + </tr><tr> + <td class="tdl">shade, not under trees</td> + </tr><tr> + <td class="tdl">or the roof of a porch;</td> + </tr><tr> + <td class="tdl bb">shaded nearby scenes</td> + </tr> + </tbody> +</table> + +<p class="f110 spa2"><b>OUTDOOR EXPOSURE TABLE</b><br> +(Single Lenses)</p> + +<table class="spb1"> + <thead><tr class="bt bb"> + <th class="tdc_bott">Groups</th> + <th class="tdc"> Folding Cameras <br>Shutter Speed</th> + <th class="tdc_bott"> Stop </th> + <th class="tdc_bott"> Box Cameras </th> + </tr></thead> + <tbody><tr> + <td class="tdc">1</td> + <td class="tdc">¹/₂₅</td> + <td class="tdc">3</td> + <td class="tdc">Snapshot with middle stop</td> + </tr><tr> + <td class="tdc">2</td> + <td class="tdc">¹/₂₅</td> + <td class="tdc">2</td> + <td class="tdc">Snapshot with largest stop</td> + </tr><tr> + <td class="tdc">3</td> + <td class="tdc">¹/₂₅</td> + <td class="tdc">1</td> + <td class="tdc">Snapshot with largest stop</td> + </tr><tr class="bb"> + <td class="tdc">4</td> + <td class="tdc">1 second</td> + <td class="tdc">4</td> + <td class="tdc">1 second with smallest stop</td> + </tr> + </tbody> +</table> + +<p>MOVING OBJECTS. The briefest possible exposure must be given +to moving objects in order that the motion may be stopped. Consequently +such pictures can be taken only in bright sunlight and in most cases +the largest stop opening must be used. Best results are usually +<span class="pagenum" id="Page_34">[Pg 34]</span> +obtained by taking the picture from somewhat in front of the subject +and a little to one side or perhaps at about a 45 degree angle. In this +way the actual movement of the subject in relation to the camera is +not so apparent as at right angles, and the perspective will be more +pleasing. It is necessary to work back at some little distance if the +subject is moving rapidly. If the shutter speed is ¹/₁₀₀ it will be +necessary to get back perhaps 75 or 100 feet. On the other hand if a +focal plane shutter is being used in connection with an f.4.5 lens, +then an exposure of from ¹/₅₀₀ to ¹/₁₀₀₀ will enable the worker to get +somewhat closer and get sharp images of automobile races or similar +subjects.</p> + +<p>INTERIORS. Stop 16 or smaller should ordinarily be used for +interiors in order to get nearby objects and those at the furthest side +of the room sharp at the same time. Do not include any objects in the +picture that are very close to the camera. The exposure for interiors +varies widely according to different conditions but the following table +for use with stop 16 (next to largest stop on single lens cameras) may +be found useful as a guide:</p> + +<div class="blockquot"> +<p>White walls and more than one window—Bright sun outside, 4 seconds; +cloudy bright, 20 seconds; hazy sun, 10 seconds; cloudy dull, 40 +seconds.</p> + +<p>White walls and only one window—Bright sun outside, 6 seconds; +cloudy bright, 30 seconds; hazy sun, 15 seconds; cloudy dull, 60 +seconds.</p> + +<p>Medium colored walls and hangings and more than one window—Bright +sun outside, 8 seconds; cloudy bright, 40 seconds; hazy sun, 20 +seconds; cloudy dull, 80 seconds.</p> + +<p>Medium colored walls and hangings with only one window—Bright sun +outside, 12 seconds; cloudy bright, 60 seconds; hazy sun, 30 seconds; +cloudy dull, 120 seconds. +<span class="pagenum" id="Page_35">[Pg 35]</span></p> + +<p>Dark colored walls and hangings and more than one window—Bright sun +outside, 20 seconds; cloudy bright, 20 seconds; hazy sun, 40 seconds; +cloudy dull, 2 minutes, 40 seconds.</p> + +<p>Dark colored walls and hangings and only one window—Bright sun +outside, 40 seconds; cloudy bright, 2 minutes, 40 seconds; hazy sun, 80 +seconds; cloudy dull, 5 minutes, 20 seconds.</p> +</div> + +<h3>HOME PORTRAITURE</h3> + +<p>Excellent home portraits can often be made—pictures that will reveal +the personality of the subject—in the unconventional surroundings of +the home. In order to have the exposure time cut down to a minimum so +that the subject will not move or have a set expression, a large stop +opening should be used and the subject be placed close to a window. +The most pleasing results are usually obtained when the light falls at +about a 45 degree angle.</p> + +<p>Too much posing is ruinous, especially in the case of children. They +appear at their best when unconscious of the presence of the camera. +It is very important that neither the hands nor feet or other portions +of the subject project out too much toward the camera or they will +appear too large in proportion to the remainder of the body. This is +particularly true when using a short focus lens and working up close to +get a large image.</p> + +<p>By following out the diagram, (<a href="#FIG_6">Figure 6</a>), a good +plain lighting is obtained: +<span class="pagenum" id="Page_36">[Pg 36]</span></p> + +<table id="FIG_6" class="spb1"> + <tbody><tr> + <td class="tdc" rowspan="7"> <img src="images/figure_6.jpg" alt="" width="250" height="274" > + <p class="f120"><b>Fig. 6</b></p></td> + <td class="tdl_ws2">A</td> + <td class="tdl_ws1">Subject</td> + </tr><tr> + <td class="tdl_ws2">A-1</td> + <td class="tdl_ws1">Direction of Face</td> + </tr><tr> + <td class="tdl_ws2">A-2</td> + <td class="tdl_ws1">Direction of Body</td> + </tr><tr> + <td class="tdl_ws2">B</td> + <td class="tdl_ws1">Camera</td> + </tr><tr> + <td class="tdl_ws2">C</td> + <td class="tdl_ws1">Reflector</td> + </tr><tr> + <td class="tdl_ws2">D</td> + <td class="tdl_ws1">Window</td> + </tr><tr> + <td class="tdl_ws2">E</td> + <td class="tdl_ws1">Background (if used)</td> + </tr> + </tbody> +</table> + +<p>It will be noticed that the subject is placed even with the edge of the +window or a little back of it and about as far into the room as the +window is wide. The body is turned somewhat away from the light and +then the face turned back into it until a v-shaped patch of light is +noticed on the cheek. This will give roundness to the features. A sheet +or newspaper may be used to reflect light onto the shadow side of the +subject. Enough reflected light must be used to show detail, but if too +much is used the face will appear flat.</p> + +<p>A more difficult lighting is the one shown in <a href="#FIG_7">Figure 7</a>. +<span class="pagenum" id="Page_37">[Pg 37]</span></p> + +<table id="FIG_7" class="spb1"> + <tbody><tr> + <td class="tdc" rowspan="7"> <img src="images/figure_7.jpg" alt="" width="250" height="272" > + <p class="f120"><b>Fig. 7</b></p></td> + <td class="tdl_ws2">A</td> + <td class="tdl_ws1">Subject</td> + </tr><tr> + <td class="tdl_ws2">A-1</td> + <td class="tdl_ws1">Direction of Face</td> + </tr><tr> + <td class="tdl_ws2">A-2</td> + <td class="tdl_ws1">Direction of Body</td> + </tr><tr> + <td class="tdl_ws2">C</td> + <td class="tdl_ws1">Reflector</td> + </tr><tr> + <td class="tdl_ws2">D</td> + <td class="tdl_ws1">Window</td> + </tr><tr> + <td class="tdl_ws2">E</td> + <td class="tdl_ws1">Window (for general illumination)</td> + </tr><tr> + <td class="tdl_ws2">F</td> + <td class="tdl_ws1">Background (if used)</td> + </tr> + </tbody> +</table> + +<p>A back lighting of this type is much used in showing movie effects. +Because of taking the picture toward a window it is much more difficult +than the plain lighting. It may be necessary to use a lens hood to keep +the excess light from the window from striking the lens, producing a +fogged appearance.</p> + +<p><i>Flashlight</i> if properly controlled is one of the best sources +of illumination for home use. The light is available on dark days and +evenings, and as the flash occupies but a fraction of a second, there +is not much danger of movement. The lighting should be arranged the +same as shown in <a href="#FIG_6">Figure 6</a>, the flash taking the +place of the window.</p> + +<hr class="chap x-ebookmaker-drop"> + +<div class="chapter"> +<p><span class="pagenum" id="Page_38">[Pg 38]</span></p> + <h2 class="nobreak">CHAPTER IV<br> +<span class="h_subtitle">DEVELOPING THE NEGATIVE</span></h2> +</div> + +<p>After exposure, the film or plate shows no visible change but the +“latent image” is there and by the aid of suitable chemicals and +solutions it can be brought out and made visible or in other words be +“developed.” Such solutions are termed developers.</p> + +<p>CHEMICAL PROCESS. This consists in the removal of the bromine +or chlorine from the silver bromide or silver chloride of the emulsion +where the light has acted, so as to leave the grains of metallic silver +which constitute the photographic image.</p> + +<p>Of the <i>developing agents</i> which are capable of bringing out the +image, pyro, hydroquinone and Elon are perhaps the most commonly used +for negatives, although Elon is seldom used except in connection with +one or the other.</p> + +<p>Although one of the oldest developers, pyro has long been considered +one of the best for the development of films and plates. It surpasses +other developers in the control it gives over the printing quality of +negatives as the color can easily be varied from a blue-black to a +slightly olive or yellowish tone. A slight stain image in addition to +the silver image is desirable as thus the negatives will not need to +be so dense as though they were blue-black. The present tendency is to +use pyro either in connection with Elon or with Elon and hydroquinone. +Beginners are likely to get the negatives a too decided yellow; also +<span class="pagenum" id="Page_39">[Pg 39]</span> +pyro if somewhat oxidized will stain the finger nails. An +Elon-Hydroquinone combination is one of the most popular developers, +and being non-staining it is especially good for tray development.</p> + +<p>A solution of pyro, Elon, or hydroquinone and water, will develop so +slowly that an <i>alkali</i> such as sodium carbonate is added to speed +up the action. In the presence of an alkali, however, the developing +agent quickly oxidizes, making the solution somewhat colored. +To prevent this oxidation, a <i>preservative</i> such as sodium +sulphite is added which keeps the developer clear without otherwise +affecting its properties. In order to minimize the tendency to fog +(the development of the unexposed grains of silver salts), a trace of +potassium bromide, a <i>restrainer</i>, is usually added.</p> + +<h3>TANK DEVELOPMENT</h3> + +<div class="figcenter"> + <img id="FIG_8" src="images/figure_8.jpg" alt="" width="600" height="472" > + <p class="f120"><b>Fig. 8</b></p> +</div> + +<p>Within recent years the tank method has come to be preferred by the +majority of workers. If <i>roll film</i> is being used, a special tank +developing machine consisting of a wooden box, a lightproof apron, +transferring reel, and metal solution cup will be necessary (<a href="#FIG_8">Fig. 8</a>). +<span class="pagenum" id="Page_40">[Pg 40]</span> +No dark room is required. The film is wound into the apron according +to instructions and transferred to the solution cup where it is +left in the developer for a predetermined time. This is a logical +scientific method, development being continued for a definite time in +a solution of a given strength at a known temperature. It will produce +a technically correct negative and in the hands of the average person +will no doubt give the highest percentage of good results. If the +exposure is at all within the latitude of the film, the negatives will +be of proper contrast, differing in density according to the exposure +and although requiring different printing times will give prints of +similar quality.</p> + +<p><i>Film packs</i> may also be developed in special tanks but a dark +room is necessary when loading them into the tank.</p> + +<p><i>Cut films</i> and <i>plates</i> are usually developed in open tanks +and this operation must be carried on in the dark room. The work may be +done either by the time and temperature system or the inspection method.</p> + +<h3>TRAY DEVELOPMENT</h3> + +<p>Tray development is not usually considered as convenient a method as +tank development but it has its advantages and is used by many workers. +Not only does it give an insight into the actual process, but it +affords an opportunity for the pictorial worker to secure results other +than an exact representation of the subject. Tray development must +be carried on in a dark room which is entirely free from white light +and which is illuminated only by a light such as given by a Brownie +Safelight Lamp when fitted with a Series 2 Safelight.⁠<a id="FNanchor_6_6" href="#Footnote_6_6" class="fnanchor">[6]</a></p> + +<p><span class="pagenum" id="Page_41">[Pg 41]</span> +Four trays are necessary, one for clear water, one for the developer, +one for a rinse bath, and one for the fixing bath.</p> + +<p>Many workers prefer to purchase their chemicals made up in small +packages and ready for use with only the addition of water. This is a +very convenient method. Others are interested more in the science of +photography, and prefer to make up their own solutions from formulas. +Of the many good formulas available but one will be given here⁠<a id="FNanchor_7_7" href="#Footnote_7_7" class="fnanchor">[7]</a>:</p> + +<p class="f110"><i>Elon-Hydroquinone Tray Developer</i></p> + +<table class="spb1"> + <tbody><tr> + <td class="tdl">Water (about 125° F.)  </td> + <td class="tdr_wsp">8</td> + <td class="tdl_wsp">ounces</td> + </tr><tr> + <td class="tdl">Elon</td> + <td class="tdr_wsp">22</td> + <td class="tdl_wsp">grains</td> + </tr><tr> + <td class="tdl">Sodium sulphite</td> + <td class="tdr">1½</td> + <td class="tdl_wsp">ounces</td> + </tr><tr> + <td class="tdl">Sodium bisulphite</td> + <td class="tdr_wsp">15</td> + <td class="tdl_wsp">grains</td> + </tr><tr> + <td class="tdl">Hydroquinone</td> + <td class="tdr_wsp">42</td> + <td class="tdl_wsp">grains</td> + </tr><tr> + <td class="tdl">Sodium carbonate</td> + <td class="tdr_wsp">82</td> + <td class="tdl_wsp">grains</td> + </tr><tr> + <td class="tdl">Potassium bromide</td> + <td class="tdr_wsp">12</td> + <td class="tdl_wsp">grains</td> + </tr><tr> + <td class="tdl">Water to make</td> + <td class="tdr_wsp">16</td> + <td class="tdl_wsp">ounces</td> + </tr> + </tbody> +</table> + +<p>For use dilute with equal parts of water. The temperature should be 65 +degrees Fahrenheit.</p> + +<p><i>Development.</i> If roll film is being used it is first detached +from the red paper on the roll, and then, one end being held in each +hand, it is passed face down through a tray of clear water several +times to eliminate air bubbles and to prevent curling. Next it is +passed back and forth through the developer in the same manner, this +motion being continued until development is complete.</p> + +<p>Ordinarily the films should remain in the developer until the picture +<span class="pagenum" id="Page_42">[Pg 42]</span> +is about faded out on the side where it first appeared and begins to +show quite well on the back. Longer development will not only make +the negative denser but will result in more contrast or a greater +difference in density between the highlights and shadows. Therefore +development should be continued until the negative is of the proper +density and contrast to give good prints on the type of printing paper +which is being used. Naturally it will take some experience to know +just when the correct point is reached. The negatives may be examined +by holding them up in front of the safelight lamp but they should not +be held there for more than a few seconds at a time.</p> + +<p>Because of the extra transparent coating on film packs, the purpose +of which is to lessen the possibility of scratching the emulsion +on drawing the tabs, about 1–3 longer development is required than +for roll film. Super-speed film also requires longer development. +Panchromatic film, being sensitive to all colors, must be developed in +total darkness or by the aid of a deep green light.</p> + +<p><i>Rinsing.</i> When developed, films are rinsed for a few seconds in +clear water and then transferred to the fixing bath. The following +rinse bath may be used instead of clear water and has the advantage that +it will not only harden the films but will stop development at once.</p> + +<table class="spb1"> + <tbody><tr> + <td class="tdl">Water</td> + <td class="tdr_wsp">16</td> + <td class="tdl_wsp">ounces</td> + </tr><tr> + <td class="tdl">Potassium chrome alum<span class="ws3"> </span></td> + <td class="tdr_wsp">½</td> + <td class="tdl_wsp">ounce</td> + </tr> + </tbody> +</table> + +<p>The negatives should be left in this bath for two or three minutes, +being moved about especially when first being immersed. The hardening +bath should be renewed frequently.</p> + +<p><i>Fixing.</i> After the negatives are developed the particles of +<span class="pagenum" id="Page_43">[Pg 43]</span> +silver bromide which were not affected by the light are still sensitive +and so must be removed by a process called “fixation.” Here the hypo +(sodium thiosulphate) combines with the unexposed grains of silver +bromide or other silver salts to form a compound which is soluble in +water and therefore which can be removed by washing.</p> + +<p>Either a chrome alum fixing bath or an acetic acid fixing bath may be +used, but the latter will be given here as this formula is suitable for +prints as well as negatives.</p> + +<p class="f110"><i>Acetic Acid Fixing Bath</i></p> + +<table class="spb1"> + <tbody><tr> + <td class="tdc fs_120" colspan="3"><b>A</b></td> + </tr><tr> + <td class="tdl">Hypo</td> + <td class="tdr">16</td> + <td class="tdl_wsp">ounces</td> + </tr><tr> + <td class="tdl">Water to make</td> + <td class="tdr">64</td> + <td class="tdl_wsp">ounces</td> + </tr><tr> + <td class="tdl_ws1" colspan="3">When thoroughly dissolved, add</td> + </tr><tr> + <td class="tdl_ws2" colspan="3">the following hardening solution:</td> + </tr><tr> + <td class="tdl">Water (about 125° F.)</td> + <td class="tdr">5</td> + <td class="tdl_wsp">ounces</td> + </tr><tr> + <td class="tdl">Sodium sulphite</td> + <td class="tdr">1</td> + <td class="tdl_wsp">ounce</td> + </tr><tr> + <td class="tdl">Acetic acid (28%)</td> + <td class="tdr">3</td> + <td class="tdl_wsp">ounces</td> + </tr><tr> + <td class="tdl">Potassium alum</td> + <td class="tdr">1</td> + <td class="tdl_wsp">ounce</td> + </tr> + </tbody> +</table> + +<p>The chemicals should be dissolved in the order given using water at +about 125° F. Be sure that the sodium sulphite has completely dissolved +before adding the acetic acid. After the sulphite-acid solution has +been thoroughly mixed, add the potassium alum and stir until completely +dissolved. Add the cold hardener solution (B) slowly to the cold hypo +solution (A), stirring the latter continually.</p> + +<p>The negatives when first being placed in the fixing bath should be +moved about for a few seconds and then occasionally during the entire +time of fixation. This should be for about 15 minutes or for twice as +long as it takes to clear them of the white milky appearance. If not +kept separated properly or if removed too soon the negatives will later +<span class="pagenum" id="Page_44">[Pg 44]</span> +discolor, probably showing yellow stain. Sixty-four ounces of this bath +will completely fix the equivalent of 200 3¼ x 5½ negatives if the Alum +Rinse Bath is used.</p> + +<p><i>Washing.</i> When removed from the fixing bath, negatives contain in +the gelatin a number of chemicals which must be removed if permanency +is to be assured. These include the hypo and other chemicals of the +fixing and hardening bath and also other compounds formed by the +reaction between the hypo and silver salts, and also possibly some +carried over from the developer. Washing should be for 30 minutes in +running water or for five minutes each in six changes of water.</p> + +<p><i>Drying.</i> Superfluous water together with any grains of dirt from +the wash water should be removed from the film or plate by swabbing +gently with absorbent cotton which has been saturated with water. Roll +film may be hung up to dry in such a way that neither side touches +anything. Drying should take place where there is circulation of warm, +dry air, but not in the sunlight or where the temperature is too high +or the emulsion may melt. Neither should the negatives be dried in a +dusty location as any specks of dust will show up as white spots when +the negatives are printed.</p> + +<h3>NEGATIVE DEFECTS</h3> + +<p>After the process of development is complete and the negatives are dry, +it may be found that some of them have been underexposed or overexposed +or underdeveloped or overdeveloped. The following table indicates the +results that should be expected from variations in exposure and development. +<span class="pagenum" id="Page_45">[Pg 45]</span></p> + +<table class="spb1"> + <thead><tr> + <th class="tdc">Exposure </th> + <th class="tdc">Development</th> + <th class="tdc">Result</th> + </tr></thead> + <tbody><tr> + <td class="tdl">Under</td> + <td class="tdl_ws1">Under</td> + <td class="tdl_wsp">Very thin and weak, only highlights visible.</td> + </tr><tr> + <td class="tdl">Under</td> + <td class="tdl_ws1">Normal</td> + <td class="tdl_wsp">Thin, shadow detail weak or lacking.</td> + </tr><tr> + <td class="tdl">Under</td> + <td class="tdl_ws1">Over</td> + <td class="tdl_wsp">Thin shadows, dense highlights,</td> + </tr><tr> + <td class="tdl"> </td> + <td class="tdl_ws1"> </td> + <td class="tdl_ws1">very contrasty, often fog.</td> + </tr><tr> + <td class="tdl">Normal</td> + <td class="tdl_ws1">Under</td> + <td class="tdl_wsp">Thin, flat, detail throughout but weak.</td> + </tr><tr> + <td class="tdl">Normal</td> + <td class="tdl_ws1">Normal</td> + <td class="tdl_wsp">Correct density and contrast good</td> + </tr><tr> + <td class="tdl"> </td> + <td class="tdl_ws1"> </td> + <td class="tdl_ws1">detail in all parts.</td> + </tr><tr> + <td class="tdl">Normal</td> + <td class="tdl_ws1">Over</td> + <td class="tdl_wsp">Rather dense with too much contrast;</td> + </tr><tr> + <td class="tdl"> </td> + <td class="tdl_ws1"> </td> + <td class="tdl_ws1">detail may be obscured in highlights.</td> + </tr><tr> + <td class="tdl"></td> + <td class="tdl_ws1"></td> + <td class="tdl_wsp"></td> + </tr><tr> + <td class="tdl">Over</td> + <td class="tdl_ws1">Under</td> + <td class="tdl_wsp">Somewhat thin, very flat, full detail.</td> + </tr><tr> + <td class="tdl">Over</td> + <td class="tdl_ws1">Normal</td> + <td class="tdl_wsp">Rather dense, somewhat flat,</td> + </tr><tr> + <td class="tdl"></td> + <td class="tdl_ws1"></td> + <td class="tdl_ws1">plenty of detail in all parts.</td> + </tr><tr> + <td class="tdl">Over</td> + <td class="tdl_ws1">Over</td> + <td class="tdl_wsp">Very black or nearly opaque,</td> + </tr><tr> + <td class="tdl"> </td> + <td class="tdl_ws1"> </td> + <td class="tdl_ws1">shadows too heavy, detail lost in</td> + </tr><tr> + <td class="tdl"> </td> + <td class="tdl_ws1"> </td> + <td class="tdl_ws1">the highlights.</td> + </tr> + </tbody> +</table> + +<p>Sometimes negatives are defective in some way and need treatment +before being printed. Those that are too thin and flat, having a +short scale of contrast as the result of underdevelopment, should +be <i>intensified</i>. On the other hand if the negatives have +been overexposed or overdeveloped they should be <i>reduced</i>. +Formulas for these processes are given in <i>Elementary Photographic +Chemistry</i>.</p> + +<hr class="chap x-ebookmaker-drop"> + +<div class="chapter"> +<p><span class="pagenum" id="Page_46">[Pg 46]</span></p> + <h2 class="nobreak">CHAPTER V<br> +<span class="h_subtitle">PRINTING THE PICTURE</span></h2> +</div> + +<p>Printing is perhaps the most interesting of all the phases of +photographic work. While correct lighting, exposure, and negative +making cannot be too strongly emphasized, it is after all the finished +print that has been the end in view through each successive step.</p> + +<h3>PRINTING PAPERS</h3> + +<p>PRINTING-OUT PAPERS. The earliest printing paper, plain silver +paper, was introduced by Fox Talbot about 1840. This was followed +by albumen papers, examples being found in the family albums of a +generation ago. Later came the silver chloride papers of the collodion +and gelatin types. In addition to these printing-out papers are others +such as platinum, and carbon, both of which are used quite largely +by pictorial workers. Blue-prints, which are now mainly used for +architect’s drawings, are made by one of the simplest of processes. +After exposure to sunlight through the negative until the image is +visible except in the highlights, washing in water completes the +process, as development and fixing are not required.</p> + +<p>DEVELOPING PAPERS. These are used almost exclusively at the +present time. They are very similar to films except in regard to the +kind of support and in the speed. Papers for contact printing usually +have silver chloride for the sensitive silver salt. These are not as +fast papers as those used for enlarging, which more often have silver +bromide for the sensitive compound. +<span class="pagenum" id="Page_47">[Pg 47]</span></p> + +<p>SELECTION OF PAPER. The multiplicity of papers available +presents a valuable means of producing not only distinctive work but +also getting out that which is best technically and artistically from +every negative. Photographic papers are made in both <i>single</i> and +<i>double weight</i>, the former being well suited to small prints and +those which are to be mounted flat; the latter being more desirable for +post cards, for prints with borders that are to be left unmounted and +for professional work that is to be placed in folders.</p> + +<p>Emulsions are usually coated on a white or buff stock though +occasionally on a cream or ivory base. Printing papers are made in many +<i>surfaces</i>—glossy, semi-gloss, semi-matte, velvet, smooth-matte, +slightly rough, rough lustre, rough matte and others. If something out +of the ordinary is wanted there are papers with silk, linen and canvas +surfaces as well as emulsions on tissue, parchment and canvas. The +semi-matte, and velvet surfaces are preferred by many, although the +brilliant glossy prints are best for reproduction. Matte papers are +used for a large proportion of portraits.</p> + +<p><i>Contrast.</i> As the print is made by allowing light to shine +through the negative on to a piece of sensitive paper with which +it is placed in contact it follows that a very thin portion of the +negative will result in dark shadows in the print. Similarly over-dense +highlights of the negative will hold back so much of the light that the +lightest parts of the print will be perfectly white. The professional +photographer produces negatives of reasonable uniformity and therefore +professional papers are usually made with only one degree of contrast. +The amateur on the other hand works under such widely varying +conditions that it is almost impossible to secure uniform negatives. So +<span class="pagenum" id="Page_48">[Pg 48]</span> +his printing papers are made in several degrees of contrast, usually +three or four, to take care of the different types of negatives. In the +case of papers such as Velox or Azo, having contrasts numbered from one +(the softest) to four (the most contrasty), the following table should +be of help:</p> + +<div class="blockquot"> +<p class="neg-indent">No. 1.—A very soft paper used when printing from +contrasty negatives, or when soft effects are wanted.</p> + +<p class="neg-indent">No. 2.—A medium contrast paper used for average +negatives. Portrait papers are of about this contrast.</p> + +<p class="neg-indent">No. 3.—A more contrasty paper desirable for weak, +thin negatives.</p> + +<p class="neg-indent">No. 4.—A very contrasty paper for negatives that +are thin and flat. Also used where much contrast is wanted as when +making pictures of printed matter, line drawings, and maps.</p> +</div> + +<p>A print to be technically perfect must correctly reproduce the +variations in light and shade of the original subject in their proper +relation and depth. In other words, a paper should be selected which +is of such contrast that when printed, no portion of the picture will +be absolutely white without detail and none will be completely black, +obliterating detail. However, the scale of tones should be as long as +possible without losing this detail.</p> + +<h3>PRINTING PROCESS</h3> + +<p>The necessary materials for making prints are few in number and simple +in character. Developing and fixing solutions as well as a short stop +bath, and water for washing and prints are of course essential and +should be ready before starting. As the printing papers are sensitive +to white light the work must be done in a very subdued light or in a +dark room lighted by a safelight lamp fitted with a yellow safelight. +<span class="pagenum" id="Page_49">[Pg 49]</span></p> + +<p>EXPOSURE. The negative is placed upon the glass of the +printing frame or printing machine with the back or shiny side down. +Over this is placed a piece of sensitive paper with the sensitized +side in contact with the dull side of the negative and then the back +of the frame is replaced or the top of the printing machine pushed +down. With the frame the exposure is accomplished by holding it a few +inches from an electric light bulb or other light source for a few +seconds. The time of the exposure will have to be found by experiment. +With amateur papers such as Velox, the time of exposure must be such +that the print will develop up to the proper depth in about 45 seconds +in the developer designed for it at a temperature of 70 degrees. +Portrait papers usually require about 1½ minutes for full development +and enlarging papers may require still longer, in certain cases. If it +is found that upon development for the proper time that the print is +too light, it is evident that the exposure has been insufficient and +must be increased for the next print. On the other hand if the print +develops up to the proper depth too quickly, the exposure has been +too great and the print will be mottled and muddy. When making the +exposures, there is of course a good opportunity for dodging or holding +back certain parts of the picture. Also, there is endless opportunity +for making vignettes, borders, combination prints and other types that +are not especially difficult but which cannot be described in a book +of this size. The reader is urged to consult some more comprehensive +work.⁠<a id="FNanchor_8_8" href="#Footnote_8_8" class="fnanchor">[8]</a></p> + +<p>DEVELOPMENT. The function of the developer and the chemistry +of development are the same as for negatives and need not be repeated. A +<span class="pagenum" id="Page_50">[Pg 50]</span> +Metol (Elon)—hydroquinone combination (MQ) is now almost universally +used. Sodium carbonate has the same function as in the negative +developer but the sodium sulphite here largely acts as a preservative. +Potassium bromide is the chemical in the print developer that controls +the color. Enough bromide must be used to prevent fog or development +of the unexposed grains of silver salts, and this gives a print of a +blue-black color which if sepia-toned will tend to be purple. A larger +quantity under similar conditions of development gives an olive toned +black and white print which is likely to tone to a yellow sepia.</p> + +<p>The <i>formula</i> recommended by the manufacturer should always be +used. A specimen formula (Velox) is given:</p> + +<table class="spb1"> + <tbody><tr> + <td class="tdl">Water (about 125° F.)</td> + <td class="tdr_wsp">8</td> + <td class="tdl">ounces</td> + </tr><tr> + <td class="tdl">Elon</td> + <td class="tdr_wsp">22</td> + <td class="tdl">grains</td> + </tr><tr> + <td class="tdl">Sodium sulphite (powdered)</td> + <td class="tdr_wsp">¾</td> + <td class="tdl">ounce</td> + </tr><tr> + <td class="tdl bb">Hydroquinone </td> + <td class="tdr_wsp bb">87</td> + <td class="tdl bb">grains</td> + </tr><tr> + <td class="tdl bb" rowspan="2">Sodium carbonate (powdered)  </td> + <td class="tdr_wsp">1</td> + <td class="tdl">ounce</td> + </tr><tr> + <td class="tdr_wsp bb">55</td> + <td class="tdl bb">grains</td> + </tr><tr> + <td class="tdl">Potassium bromide</td> + <td class="tdr_wsp">13</td> + <td class="tdl">grains</td> + </tr><tr> + <td class="tdl">Water to make</td> + <td class="tdr_wsp">16</td> + <td class="tdl">ounces</td> + </tr> + </tbody> +</table> + +<p>For use, take Stock Solution 1 part, water 1 part. Develop 45 seconds +at 70° F.</p> + +<p>If placed in bottles filled to the neck and tightly corked it will keep +for several weeks.</p> + +<p><i>Method of Development.</i> Four trays containing respectively +developer, short stop bath, fixing bath, and water, arranged in that +order should be ready before starting to print. The same type of fixing +bath as recommended for negatives should be used. The short stop bath +consists of water 16 ounces and acetic acid (28%) ¾ ounce.</p> + +<p>After the exposure is made, the tray containing the <i>developer</i> is +<span class="pagenum" id="Page_51">[Pg 51]</span> +tipped to one side and the print slid in face up from the high side of +the tray which is immediately tipped the other way causing the solution +to quickly cover the entire print. The print should be left in the tray +which is rocked slowly to secure evenness of development until within +about 5 seconds or so of the completion of the process. Then while the +print is held up to drain it can easily be seen when the proper depth +is reached. It should immediately be transferred to the short stop bath.</p> + +<p>Development should be carried on for the length of time indicated +as correct by the manufacturer of the printing paper and at the +temperature recommended. After some experience it is perhaps better to +learn to develop by inspection. Correctly exposed prints are properly +developed to the correct depth when all the light affected particles +have been reduced or when the light action seems to stop. If the print +becomes too dark before it seems to pause in development, then it has +been overexposed. If it must remain in the developer for some time in +an attempt to force up the image, the print will become discolored.</p> + +<p>The print when placed in the <i>short stop bath</i> should be moved +about for two or three seconds and should then be transferred to the +fixing bath, or it may remain until a few more prints are made. A short +stop bath will stop development immediately and will also prevent +the alkali and carbonate from being carried over into the fixing +bath. <i>After the fingers have been in the short stop bath or fixing +bath, they must be washed and dried before being placed back in the +developer.</i></p> + +<p>FIXATION. The prints should be fixed in 15 minutes. A long +immersion may cause bleaching, or discoloration if the bath is too +<span class="pagenum" id="Page_52">[Pg 52]</span> +warm. The prints must be turned over and separated a number of times +during the process of fixation to be sure that all the silver salts +are eliminated. If they are not thoroughly fixed they may turn pink +and gradually fade. If the rinse bath has been used, 64 ounces of the +fixing bath should properly fix 200 3¼ × 5½ prints. Should the fixing +bath become milky in appearance it should be discarded at once.</p> + +<p>WASHING. Washing prints by hand is perhaps the most certain +method of eliminating chemicals from the paper and emulsion. Prints +are placed in a tray of clear water and after four or five minutes are +transferred one at a time to another tray of clear water of similar +temperature; the first tray is again filled with clear water and the +process is repeated until the prints have been passed through 10 or 12 +changes of water. If the change in temperature from one wash water to +another or from the developer to fixing bath or from the fixing bath to +the wash water, is very considerable, blisters are likely to result. +If running water is available and the prints are kept separated, they +should properly wash in about one hour.</p> + +<p>DRYING. Prints except those having a glossy surface should +be dried face down on photo lintless blotters or on cheese cloth +stretchers. Glossy prints are rolled into contact on ferrotype tins and +when dry have a very smooth shiny surface. Drying machines are used in +commercial photo finishing establishments where it is necessary to turn +out hundreds or even thousands of prints a day.</p> + +<p>After the prints are dry they are likely to have a decided curl inward. +They can be straightened by drawing them sharply over the back of a +table, although there is danger of cracking the emulsion. A better way +is to dampen the backs slightly with a wet sponge or cotton and then +<span class="pagenum" id="Page_53">[Pg 53]</span> +place them between heavy lintless cardboards under a few pounds +pressure until dry again.</p> + +<h3>ENLARGING</h3> + +<p>Enlargements are in no way materially different from ordinary prints +except that a faster paper is used and the image is formed by +projection through a lens as when being made in the camera, instead +of by contact. With the advent of the modern fast enlarging papers of +contact quality, this method of printing has become so simplified that +beautiful enlargements of any reasonable size can easily and quickly be +made from small negatives of good quality. Thus the ambitious worker +with his ever present Vest Pocket Kodak fitted with an anastigmat lens +is always ready for any emergency, knowing that whenever a worthy +negative is secured it may be used to produce a large picture the equal +of a contact print from a larger camera.</p> + +<p>For a long time fixed focus enlarging machines or focusing machines +were used. However, the Automatic Focusing machines are so much more +convenient that they are coming into general use. Being automatic in +focus much time is saved over the kind where it is necessary to attend +to getting the proper sized image and the correct focus at the same +time. Some of these cameras have supplementary lenses which may be +used over the regular lens when softness and diffusion are wanted. The +process of development, fixing, washing and drying is similar to that +of making contact prints.</p> + +<h3>TONING⁠<a id="FNanchor_9_9" href="#Footnote_9_9" class="fnanchor">[9]</a></h3> + +<p><span class="pagenum" id="Page_54">[Pg 54]</span> +For most photographic subjects nothing is more satisfactory than a +good black and white print. Occasionally, however, such a subject as +an autumn landscape is more truthfully rendered in a warmer tone while +pictures of people are often preferred in sepia tones as being more +true to life. Of the two principal methods of producing sepia tones, +the redevelopment and the hypo-alum, the former is usually preferred +for amateur work as it is more simple.</p> + +<h3>FINISHING THE PICTURE⁠<a id="FNanchor_10_10" href="#Footnote_10_10" class="fnanchor">[10]</a></h3> + +<p>Keeping prints loose in a box or drawer is a most unsatisfactory method +of preservation, as they soon become dirty or lost. Mounting them in +folders or on card mounts is better but for average amateur work this +is not so good as keeping them in albums.</p> + +<p>When selecting mounts, it is well to remember that a light mount will +make a picture appear darker and consequently should be used for a +print that is too light. Similarly a dark print should be placed in a +still darker mount. Black and white prints generally look best on gray +mounts and sepia on brown ones.</p> + +<p>Nearly all prints are improved by judicious <i>trimming</i>. Anything +that does not help center the interest should be eliminated. Vertical +and horizontal lines that are not true should be corrected whenever +possible. A good, clean cut edge along with square corners can be +secured by the use of a regular trimming board.</p> + +<p>If prints are to be <i>dry mounted</i>, they should not be trimmed +until after the mounting tissue is attached to the print. Dry mounting +has the decided advantage that prints can be mounted perfectly flat on +thin mounts or album leaves. It is very easily done and does not get +<span class="pagenum" id="Page_55">[Pg 55]</span> +the print or mount soiled and the print is protected from possible +moisture and injurious chemicals in the mount. A piece of dry mounting +tissue is attached to the back of the print by touching it in a couple +of places with a hot iron. The print is now turned face up and with the +adhering tissue is trimmed to the proper size. Next it is placed in +position on the mount, covered with a thin card and put under pressure +for a few seconds in a dry mounting press, or a flat iron may be used.</p> + +<p>After the print is mounted it is often necessary to do some +<i>spotting</i>. Any small white spots are filled up using a No. 1 +sable brush and a card of spotting colors.</p> + +<p>Many prints are made more effective by <i>hand coloring</i>. Tinting +with water colors is perhaps the most popular method, although studio +work is often done with oil or pastel colors.</p> + +<hr class="chap x-ebookmaker-drop"> + +<div class="chapter"> +<p><span class="pagenum" id="Page_56">[Pg 56]</span></p> + <h2 class="nobreak">CHAPTER VI<br> +<span class="h_subtitle">MOTION PICTURES</span></h2> +</div> + +<p>From an economic standpoint the motion picture business, including the +manufacture of film and other materials, and the production and showing +of pictures, is one of the major industries of the country.</p> + +<p>In the past, entertainment has been the primary aim of motion pictures. +Now the field is broadening until it seems likely that their greatest +contribution to mankind will be in science, in industry, and in +education. Especially in research work are they valuable as cameras +have been devised that will take from 500 to 4000 pictures a second +of such subjects as a bullet piercing armor plate, a bird in flight, +mechanical motion, chemical action, or rapidly moving microscopic life. +The pictures can then be printed individually or can be projected as +slow motion pictures at only a fraction of the speed at which they were +taken, so the subject will seem to barely move. By analyzing motion +many extremely important facts have been learned. In industry such +pictures may be used to show where lost motion can be eliminated and +how an operation can be performed more efficiently. When it comes to +athletic sports, it is very difficult for the individual in football, +tennis or crew to realize just where his weakness lies, and what he +lacks in form, but when he sees himself on the screen as he actually +performs each individual movement, he can improve himself accordingly. +<span class="pagenum" id="Page_57">[Pg 57]</span></p> + +<p>As it is generally recognized that knowledge is more quickly gained +by the visual method than in any other way, schools, colleges and +universities are using motion pictures more and more as an aid in +teaching all kinds of subjects. Often there is no sharp line between +educational and entertainment films. Dramatic films may be found +useful for art classes; science and travel films in the study of such +subjects as physical geography, geography and history. Films showing +such interesting phases of nature study as micro-organisms, the life +history of the bee, and the emerging of the butterfly are invaluable +in teaching biology and its allied sciences. Even in the lower grades, +animated drawings and maps and other types of pictures find their places.</p> + +<h3>PRINCIPLE OF MOTION PICTURES</h3> + +<p>Motion picture cameras are arranged to take long rolls of film, often +several hundred feet in length. Standard film is 35 mm. (1⅜ inches) +wide. By turning a crank at a uniform rate of two revolutions a second, +the film is carried past the lens and eight exposures are made at +each revolution, or 16 a second, which uses about one foot of film. +A revolving shutter admits light to the film which stops during the +exposure. Each picture is made in ¹/₁₆ of a second and during this time +the shutter must open and close and a new section of film be drawn down +for the next exposure.</p> + +<p>The film is developed, fixed, washed and dried and then printed on +positive film which in turn must be developed, fixed, washed, dried and +perhaps tinted. +<span class="pagenum" id="Page_58">[Pg 58]</span></p> + +<p>The motion picture as seen on the screen is really a series or still +pictures projected at the rate of 16 a second. Each picture is on the +screen but a fraction of a second, the film not moving during this +instant. Then the rotating shutter covers the lens in the same way as +when the picture was being taken while a new view is brought down into +position. During the time between pictures, the screen is perfectly +dark, but because of “persistence of vision,” this is unnoticed so that +to the audience the projected still pictures make up the regular motion +picture with which they are familiar.</p> + +<h3>PICTURES IN THE HOME</h3> + +<p>The desire for making personal motion pictures is a very common one. +So irresistible is this appeal that almost everyone has long wished +for movies of the people who particularly interest them, movies that +they could make themselves and then show in their own homes. But until +recently there have been outstanding obstacles. Ordinary film is so +inflammable that many states have laws against its projection except in +fireproof booths. This often makes it impossible to show pictures in +a small school, church, or home. Also, standard film, which is taken +at the rate of 1 foot a second and then has to be printed on an equal +amount of positive film, makes the process expensive for those who wish +to make their own moving pictures.</p> + +<p>To overcome these disadvantages simple motion picture cameras such +as the <i>Ciné-Kodak</i> (<a href="#FIG_9">Figure 9</a>) are now made +which use only a narrow width safety film, 16 mm. (⅝ inch) wide. Some +<span class="pagenum" id="Page_59">[Pg 59]</span> +are operated by a crank the same as professional cameras; others by a +spring motor. With the type using a motor, the camera can be held in +the hands when the picture is being taken.</p> + +<div class="figcenter"> + <img id="FIG_9" src="images/figure_9.jpg" alt="" width="600" height="398" > + <p class="f120"><b>Fig. 9</b></p> +</div> + +<p>Four hundred feet of this film gives the same period of projection when +used in the <i>Kodascope</i> (<a href="#FIG_10">Figure 10</a>) as a thousand +feet of ordinary standard film, and as the film which is sent to the +manufacturer for development, is reversed to a positive by chemical +treatment, printing on a regular positive film is unnecessary. For this +reason the expense is only about ⅙ that of making standard size motion pictures.</p> + +<p>FILM LIBRARIES. Although movies made in and around the +home are so completely fascinating in themselves, nevertheless, the +Kodascope offers another feature for the home entertainer. Hundreds of +<span class="pagenum" id="Page_60">[Pg 60]</span> +thousands of feet of professionally made pictures have been leased for +use to the Kodascope Libraries, Inc.⁠<a id="FNanchor_11_11" href="#Footnote_11_11" class="fnanchor">[11]</a> +Thus it is possible to rent films to fit any type of +entertainment—comedies, dramas, animated cartoons, educational +films—everything, in fact, most suitable for home projection,—and new +films are being added continually.</p> + +<div class="figcenter"> + <img id="FIG_10" src="images/figure_10.jpg" alt="" width="600" height="444" > + <p class="f120"><b>Fig. 10</b></p> +</div> + +<hr class="chap x-ebookmaker-drop"> + +<div class="chapter"> +<p><span class="pagenum" id="Page_61">[Pg 61]</span></p> + <h2 class="nobreak">CHAPTER VII<br> +<span class="h_subtitle">SCOPE OF PHOTOGRAPHY</span></h2> +</div> + +<p>The average person thinks of photography in connection with motion +pictures, snapshots, and perhaps occasional photographs, but these are +only a small part of the total contribution photography makes to the +world.</p> + +<p>The field of photography as an avocation comes very close home to all +of us. No matter what may be our hobby, whether swimming, canoeing, +fishing, hiking, or other kindred sports, photography is a natural +ally. It is not only the interest that our friends manifest in our +pictures that justify their making. It is the pleasure we experience in +reviewing the picture record that makes photography so eminently worth +while. As time passes and details fade from memory, the pictures of the +outings so vividly recall the various scenes and incidents that we live +those joyous days over again as often as we wish.</p> + +<p>The ever increasing multiplicity of ways in which photography is used +commercially makes possible only a bare mention of some of the more +important. As a <i>business</i> it consists roughly of four types of +work—portrait, commercial, amateur finishing and motion picture work. +Through the application of photography there have been many definite +advances in observational <i>scientific investigation</i>.⁠<a id="FNanchor_12_12" href="#Footnote_12_12" class="fnanchor">[12]</a> +<span class="pagenum" id="Page_62">[Pg 62]</span> +Photography is made use of in law courts as evidence in the case +of accidents and in deciphering charred records; in dentistry and +medicine it enables the doctor through the X-ray to make a definite +diagnosis and have records for analysis and study. In meteorological +work a study of clouds, storms and floods is made by the aid of the +camera, while the astronomer is able through the cumulative character +of light action to show stars which are so faint because of their +great distance that they are invisible even through the most powerful +telescopes. In war times photography is the leading factor in securing +much valuable information, airplanes equipped with special cameras +being used to locate the enemy’s position, detect camouflage, and +make aerial maps from which firing data is worked out. In efficiency +tests in the big industrial plants motion picture records are made of +the operations both of machines and men to show where excess and loss +can be eliminated so as to speed up production. The engineer and the +contractor can also check up on the work of individuals as well as make +actual records of details and show the progress made from day to day.</p> + +<p>And then there is the widespread use of pictures in the magazines and +papers both as <i>illustrations</i> and <i>advertisements</i>. There is +scarcely an article on the market which is largely advertised that is +not accompanied by a cut of some kind. In this connection it must be +pointed out the close relationship of photography and photo-engraving. +The engraver uses the photographic print to make the cut from which the +magazine and newspaper pictures are printed. +<span class="pagenum" id="Page_63">[Pg 63]</span></p> + +<p><i>Color Photography</i> is another line in which definite advances are +being made. Pictures in monochrome while quite faithfully translating +color values into shades of black and white and answering all ordinary +requirements, yet are most unsatisfactory for depicting the grandeur of +a mountain view or the sublime beauty of an evening sunset. Innumerable +processes have been brought forward from time to time and many patents +have been granted for photographic color processes. However, no method +has yet been devised for making pictures in color that even remotely +approaches the simplicity of ordinary black and white photography.</p> + +<p>The autochrome process as introduced by M. M. Lumière of Lyons, a +screen plate process, is perhaps the simplest adaptation. It consists +of a glass plate coated with a sticky varnish on which is dusted a +mixture of fine starch grains which have been dyed the three primary +colors and mixed together in suitable proportions resulting in a +colorless coating. Over this is applied a coat of water proof varnish +and then a very thin panchromatic emulsion. The exposure is made as +in the case of an ordinary plate except that the glass side is toward +the lens. By this means the exposure is made through the orange-red, +green and blue-violet starch grains which act as filters. The exposed +plate is developed for a definite time or by inspection, by the aid of +a special green safelight. After rinsing it is immersed in a reducing +solution which will dissolve out the finely divided silver forming +the negative image. When this deposit has been removed the starch +grains transmit light like those which came to them in the camera. The +<span class="pagenum" id="Page_64">[Pg 64]</span> +remainder of the silver salts not affected by the primary exposure and +development is now reduced to metallic silver. This development must +take place while the plate is exposed to a strong white light. The +plates when finished must be viewed either as transparencies or on the +screen as lantern slides.</p> + +<p><i>Color printing processes</i> are hardly practical for the average +amateur. Three negatives are made on panchromatic (color sensitive) +plates or films using orange-red, green and blue-violet process +filters. Each negative must be printed in its complementary color. The +colors in which they are printed may be obtained from pigmented papers +such as carbon; or colored inks, paints or other coloring materials may +be used. The three carbon tissues or prints are then transferred to the +same final support being cemented down in correct register. In spite +of all the difficulties attendant on color photography, even motion +pictures in colors are now possible.</p> + +<p>There have been other advances which are almost unbelievable. Objects +more than one hundred miles distant, practically invisible because +of the atmospheric haze, have been photographed by suitable color +sensitive films and filters. Pictures are made in the dark by means +of the invisible ultra-violet ray while there are great possibilities +with the infra-red rays and X-rays. With other constant developments in +all phases of photographic work, who can prophesy what the future will +bring forth?</p> + +<hr class="chap x-ebookmaker-drop"> + +<div class="footnotes"> +<p class="f150"><b>Footnotes:</b></p> + +<div class="footnote"><p class="no-indent"> +<a id="Footnote_1_1" href="#FNanchor_1_1" class="label">[1]</a> +See Photo-Miniature No. 60: <i>Who Discovered Photography</i>.</p></div> + +<div class="footnote"><p class="no-indent"> +<a id="Footnote_2_2" href="#FNanchor_2_2" class="label">[2]</a> +For a more exhaustive discussion, see Harting: <i>Optics for Photographers</i>.</p></div> + +<div class="footnote"><p class="no-indent"> +<a id="Footnote_3_3" href="#FNanchor_3_3" class="label">[3]</a> +Discussed more fully in <i>Color Films, Plates and Filters</i>. +Eastman Kodak Company.</p></div> + +<div class="footnote"><p class="no-indent"> +<a id="Footnote_4_4" href="#FNanchor_4_4" class="label">[4]</a> +See, Hammond: <i>Pictorial Composition in Photography</i>.</p></div> + +<div class="footnote"><p class="no-indent"> +<a id="Footnote_5_5" href="#FNanchor_5_5" class="label">[5]</a> +Wollensak Optical Company, Rochester, N. Y.</p></div> + +<div class="footnote"><p class="no-indent"> +<a id="Footnote_6_6" href="#FNanchor_6_6" class="label">[6]</a> +Described in <i>Modern Dark Room Illumination</i>, Eastman Kodak Co.</p> +</div> + +<div class="footnote"><p class="no-indent"> +<a id="Footnote_7_7" href="#FNanchor_7_7" class="label">[7]</a> +Those who are interested in preparing other types of formulas should +have a copy of <i>Elementary Photographic Chemistry</i> which can be +obtained free from the Eastman Kodak Co., Rochester, N. Y.</p> +</div> + +<div class="footnote"><p class="no-indent"> +<a id="Footnote_8_8" href="#FNanchor_8_8" class="label">[8]</a> +See Snodgrass: <i>The Science and Practice of Photographic Printing</i>.</p> +</div> + +<div class="footnote"><p class="no-indent"> +<a id="Footnote_9_9" href="#FNanchor_9_9" class="label">[9]</a> +For more exhaustive information on toning see Snodgrass: +<i>The Science and Practice of Photographic Printing</i>.</p> + +<p class="no-indent"><i>Elementary Photographic Chemistry.</i> Eastman Kodak Company.</p> +</div> + +<div class="footnote"><p class="no-indent"> +<a id="Footnote_10_10" href="#FNanchor_10_10" class="label">[10]</a> +See Photo-Miniature No. 188: <i>The Exhibition Print</i>.</p> +</div> + +<div class="footnote"><p class="no-indent"> +<a id="Footnote_11_11" href="#FNanchor_11_11" class="label">[11]</a> +At 35 West 42nd Street, New York City.</p> +</div> + +<div class="footnote"><p class="no-indent"> +<a id="Footnote_12_12" href="#FNanchor_12_12" class="label">[12]</a> +See <i>Photography as a Scientific Implement</i>, +published by D. Van Nostrand Company.</p> +</div> + +<div class="chapter"> +<div class="transnote bbox spa2"> +<p class="f120 spa1">Transcriber’s Notes:</p> +<hr class="r10"> +<p>Deprecated spellings or ancient words were not corrected.</p> +<p>The illustrations have been moved so that they do not break up + paragraphs and so that they are next to the text they illustrate.</p> +<p>Typographical and punctuation errors have been silently corrected.</p> +</div></div> + +</div> +<div style='text-align:center'>*** END OF THE PROJECT GUTENBERG EBOOK 77383 ***</div> +</body> +</html> diff --git a/77383-h/images/cover.jpg b/77383-h/images/cover.jpg Binary files differnew file mode 100644 index 0000000..180bb8b --- /dev/null +++ b/77383-h/images/cover.jpg diff --git a/77383-h/images/figure_1.jpg b/77383-h/images/figure_1.jpg Binary files differnew file mode 100644 index 0000000..66f2d14 --- /dev/null +++ b/77383-h/images/figure_1.jpg diff --git a/77383-h/images/figure_10.jpg b/77383-h/images/figure_10.jpg Binary files differnew file mode 100644 index 0000000..98805a0 --- /dev/null +++ b/77383-h/images/figure_10.jpg diff --git a/77383-h/images/figure_2.jpg b/77383-h/images/figure_2.jpg Binary files differnew file mode 100644 index 0000000..5f8f8c5 --- /dev/null +++ b/77383-h/images/figure_2.jpg diff --git a/77383-h/images/figure_3.jpg b/77383-h/images/figure_3.jpg Binary files differnew file mode 100644 index 0000000..35635dd --- /dev/null +++ b/77383-h/images/figure_3.jpg diff --git a/77383-h/images/figure_4.jpg b/77383-h/images/figure_4.jpg Binary files differnew file mode 100644 index 0000000..13b1279 --- /dev/null +++ b/77383-h/images/figure_4.jpg diff --git a/77383-h/images/figure_5.jpg b/77383-h/images/figure_5.jpg Binary files differnew file mode 100644 index 0000000..5154472 --- /dev/null +++ b/77383-h/images/figure_5.jpg diff --git a/77383-h/images/figure_6.jpg b/77383-h/images/figure_6.jpg Binary files differnew file mode 100644 index 0000000..ceb9f7a --- /dev/null +++ b/77383-h/images/figure_6.jpg diff --git a/77383-h/images/figure_7.jpg b/77383-h/images/figure_7.jpg Binary files differnew file mode 100644 index 0000000..ddd94e7 --- /dev/null +++ b/77383-h/images/figure_7.jpg diff --git a/77383-h/images/figure_8.jpg b/77383-h/images/figure_8.jpg Binary files differnew file mode 100644 index 0000000..98b7bbe --- /dev/null +++ b/77383-h/images/figure_8.jpg diff --git a/77383-h/images/figure_9.jpg b/77383-h/images/figure_9.jpg Binary files differnew file mode 100644 index 0000000..50f7ea9 --- /dev/null +++ b/77383-h/images/figure_9.jpg |
