diff options
Diffstat (limited to '77383-0.txt')
| -rw-r--r-- | 77383-0.txt | 1804 |
1 files changed, 1804 insertions, 0 deletions
diff --git a/77383-0.txt b/77383-0.txt new file mode 100644 index 0000000..619b4b7 --- /dev/null +++ b/77383-0.txt @@ -0,0 +1,1804 @@ +*** START OF THE PROJECT GUTENBERG EBOOK 77383 *** + + + + +Transcriber’s Notes: + +Underscores “_” before and after a word or phrase indicate _italics_ +in the original text. Small capitals have been converted to SOLID +capitals. Illustrations have been moved so they do not break up +paragraphs. + + + + + LITTLE BLUE BOOK NO. 1139 + Edited by E. Haldeman-Julius + + Photography + Self Taught + + Lloyd I. Snodgrass + + HALDEMAN-JULIUS COMPANY + GIRARD, KANSAS + + Copyright, 1926, + Haldeman-Julius Company + + PRINTED IN THE UNITED STATES OF AMERICA + + + + +CONTENTS + + + Chapter Page + + I. INTRODUCTION 5 + Simplicity of Photography—Early Stages. + + II. MATERIALS OF PHOTOGRAPHY 7 + Types of Cameras—Lenses—Stops and Shutters—Films + and Plates—Printing Papers. + + III. MAKING THE PICTURE 24 + Loading the Camera—Choice of Subject and Viewpoint + —Steps in taking the Picture—Making the Exposure— + Exposure Tables—Home Portraiture. + + IV. DEVELOPING THE NEGATIVE 38 + Chemical Process—Tank Development—Tray Development + —Negative Defects. + + V. PRINTING THE PICTURE 46 + Printing Papers—Printing Process—Enlarging—Toning + —Finishing the Picture. + + VI. MOTION PICTURES 56 + Importance—Principle—Pictures in the Home—Ciné-Kodak + —Film Libraries. + + VII. SCOPE OF PHOTOGRAPHY 61 + Business—Scientific Investigation—Illustrations— + Color Photography—Color Printing Processes—Other + Advances. + + + + +PHOTOGRAPHY SELF TAUGHT + + + + +CHAPTER I + +INTRODUCTION + + +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. + +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. + +Photography had its early beginning back in the fore part of the 18th +century[1] when the “Camera Obscura” was devised. + +[Footnote 1: See Photo-Miniature No. 60: _Who Discovered Photography_.] + +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 _hypo_ would remove the unexposed chemical, +thus fixing the image more or less permanently. + +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. + +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. + + + + +CHAPTER II + +MATERIALS OF PHOTOGRAPHY + + +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. + + +TYPES OF CAMERAS + +_Box Cameras_, 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. + +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 +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. + +_Folding cameras_, 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. + +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. + +_Reflecting cameras_ 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 +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. + +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. + +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. + + +LENSES[2] + +In order properly to understand the purpose and use of the lens it +is 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 +_reflected light_ from objects, that reaching our eyes enables us to +see them, and reaching the lens of the camera enables us to photograph +them. + +[Footnote 2: For a more exhaustive discussion, see Harting: _Optics for +Photographers_.] + +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. + +_Refraction_ 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. + +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 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 +(Figure 1) shows how the image is formed by the use of the pinhole. + +[Illustration: Fig. 1] + +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. + +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. + +[Illustration: Fig. 2] + +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. Figure 3 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. + +[Illustration: Fig. 3] + +_Focusing_ 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 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 +_focal length_. 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. + +KINDS OF LENSES. The _meniscus lens_ 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. + +A _meniscus achromatic_ 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 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. + +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. + +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 +_anastigmat_. 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 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. + +The “_Kodar_” 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. + +There are several types of lenses which are used for special purposes. +Two of the most common are wide angle lenses and telephoto lenses. +_Wide angle lenses_ 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. + +_Telephoto lenses_ 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. + +_Soft focus lenses_, 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. + + +STOPS AND SHUTTERS + +When using a camera, it is very necessary to know something about +_stops_ or diaphragm openings. + +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 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. + +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. + +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. +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. + +The following table gives a comparison of the two systems: + + F. f.4 f.5.6 f.6.3 f.8 f.11 f.16 f.22 f.32 f.45 + + U.S. 1 2 (2½) 4 8 16 32 64 128 + +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. + +The _shutter_ is a mechanical device for controlling the length of the +exposure. One of the simplest forms is shown in the following diagram: + +[Illustration: Fig. 4 + +Fig. 4 shows the position of slide B when the smallest stop is in front +of the lens.] + +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. Figure 5 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. + +[Illustration: Fig. 5] + + +FILMS AND PLATES + +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 +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. + +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. + +In addition to speed another characteristic of modern films and plates +is _latitude_. 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. + +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. + +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. + +To counteract this some plates and most films are made somewhat _color +sensitive_ 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. + +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. + +The _filter_, 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 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.[3] + +[Footnote 3: Discussed more fully in _Color Films, Plates and Filters_. +Eastman Kodak Company.] + + +PRINTING PAPERS + +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. + + + + +CHAPTER III + +MAKING THE PICTURE + + +_Loading the Camera_ + +Most hand cameras are made to take _roll film_. 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. + +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 +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. + +_Film packs_ 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. + +_Plates_ must be loaded into plate holders or into the plate magazine +in the dark room illuminated only by a safelight lamp. _Cut films_ 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. + + +CHOICE OF SUBJECT AND VIEWPOINT + +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. + + +COMPOSITION[4]. 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. + +[Footnote 4: See, Hammond: _Pictorial Composition in Photography_.] + +The first lesson to be learned is to leave out what is not required. +This is known as _selection_. 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. + +_Simplicity_ 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. + +There should be such a combining of masses, tones and lines as to +produce a pleasing whole. This is known as _harmony_ and _balance_. +Objects should be so grouped that there will not be too 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. + +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. + +In landscape photography it is not generally advisable to introduce +human figures as in nearly all cases they fail, either in costume +or in 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. + +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[5] may be used. + +[Footnote 5: Wollensak Optical Company, Rochester, N. Y.] + +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. + + +STEPS IN TAKING THE PICTURE + +After the folding camera is loaded, there are still the following steps +to be carried out in taking the picture: + + 1. See that an unexposed portion of film is + in position for the exposure. + + 2. Open the camera, and set the focus if + a focusing model is being used. + + 3. Adjust the diaphragm opening. + + 4. Set the shutter (on some types). + + 5. Hold the camera level and include the + view wanted. + + 6. Make the exposure. + +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. + +2. On the bed of most adjustable hand cameras, is a _scale_ 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. + +If the camera is 3¼ × 4¼ or smaller it may be used as if it were a +fixed focus type by extending the front to the 25 foot mark on the +focusing scale and using stop f.11 (U.S.8). + +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. + +While there are exceptions to the appended table of stops to be used, +yet it will be helpful, especially to beginners. + + f.4.5 (a) For extra rapid exposures when the light is + very good, i. e. for moving objects at 1–100 to + 1–1000 of a second. + + (b) For portraiture indoors when the light is only + fair and short time or bulb exposures are made. + + (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. + + f.6.3 (a) For quick exposures of moving objects in good + light with shutter speeds to about 1–300 second. + + (b) For slower speeds on hazy and slightly cloudy days. + + (c) For indoor home portraiture. + + 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.) + + (b) For flashlight groups. + + (c) For portraiture indoors or outdoors in the shade. + + f.11 (U.S.8) (a) For all ordinary instantaneous exposures + when the subject is in bright sunshine, using 1–25 sec. + + (b) For flashlight interiors. + + 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. + + (b) For ordinary landscapes in bright sunshine with clear + sky overhead, speed 1–25. + + (c) For interior time exposures. + + f.22 (U.S.32) (a) For instantaneous exposures of + extremely distant views. + + (b) For marine or snow scenes, or clouds in bright + sunshine, at speed 1–25. + + (c) For time exposures of interiors, and of outdoor + scenes in cloudy weather. + + f.32, f.45 (U.S.64, U.S.128) (a) For time exposures + outdoors in cloudy weather. Never used for snapshots. + +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. + +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 +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. + +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. + +6. Exposure is made by means of a lever, or cable release. + + +MAKING THE EXPOSURE + +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 +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. + + +OUTDOOR EXPOSURE TABLES (Rectilinear and Anastigmat Lenses) + + Rectilinear Anastigmat + Shutter Lenses Lenses + Groups Speed Stop Stop + + 1—Snow, marine and + beach scenes, extremely + distant landscapes ¹/₂₅ U.S. 32 f.22 + 2—Ordinary landscapes + showing sky, with a + principal object in the + foreground ¹/₂₅ U.S. 16 f.16 + 3—Nearby landscapes + showing little or no + sky, groups, street + scenes ¹/₂₅ U.S. 8 f.11 + 4—Portraits in the open + shade, not under trees + or the roof of a porch; f.7.7 or + shaded nearby scenes ¹/₂₅ U.S. 4 f.8 + + +OUTDOOR EXPOSURE TABLE (Single Lenses) + + Folding Cameras + Shutter + Groups Speed Stop Box Cameras + + 1 ¹/₂₅ 3 Snapshot with middle stop + 2 ¹/₂₅ 2 Snapshot with largest stop + 3 ¹/₂₅ 1 Snapshot with largest stop + 4 1 second 4 1 second with smallest stop + +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 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. + +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: + + White walls and more than one window—Bright sun outside, + 4 seconds; cloudy bright, 20 seconds; hazy sun, 10 seconds; + cloudy dull, 40 seconds. + + White walls and only one window—Bright sun outside, + 6 seconds; cloudy bright, 30 seconds; hazy sun, 15 seconds; + cloudy dull, 60 seconds. + + 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. + + 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. + + 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. + + 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. + + +HOME PORTRAITURE + +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. + +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. + +By following out the diagram, (Figure 6), a good plain lighting is +obtained: + +[Illustration: + + A Subject + A-1 Direction of Face + A-2 Direction of Body + B Camera + C Reflector + D Window + E Background (if used) + +Fig. 6] + +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. + +A more difficult lighting is the one shown in Figure 7. + +[Illustration: + + A Subject + A-1 Direction of Face + A-2 Direction of Body + C Reflector + D Window + E Window (for general illumination) + F Background (if used) + +Fig. 7] + +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. + +_Flashlight_ 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 Figure 6, the flash taking the place of the window. + + + + +CHAPTER IV + +DEVELOPING THE NEGATIVE + + +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. + +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. + +Of the _developing agents_ 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. + +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 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. + +A solution of pyro, Elon, or hydroquinone and water, will develop so +slowly that an _alkali_ 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 _preservative_ 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 _restrainer_, is usually added. + + +TANK DEVELOPMENT + +[Illustration: Fig. 8] + +Within recent years the tank method has come to be preferred by the +majority of workers. If _roll film_ 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 (Fig. 8). +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. + +_Film packs_ may also be developed in special tanks but a dark room is +necessary when loading them into the tank. + +_Cut films_ and _plates_ 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. + + +TRAY DEVELOPMENT + +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.[6] + +[Footnote 6: Described in _Modern Dark Room Illumination_, Eastman +Kodak Co.] + +Four trays are necessary, one for clear water, one for the developer, +one for a rinse bath, and one for the fixing bath. + +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[7]: + +[Footnote 7: Those who are interested in preparing other types of +formulas should have a copy of _Elementary Photographic Chemistry_ +which can be obtained free from the Eastman Kodak Co., Rochester, N. Y.] + +_Elon-Hydroquinone Tray Developer_ + + Water (about 125° F.) 8 ounces + Elon 22 grains + Sodium sulphite 1½ ounces + Sodium bisulphite 15 grains + Hydroquinone 42 grains + Sodium carbonate 82 grains + Potassium bromide 12 grains + Water to make 16 ounces + +For use dilute with equal parts of water. The temperature should be 65 +degrees Fahrenheit. + +_Development._ 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. + +Ordinarily the films should remain in the developer until the picture +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. + +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. + +_Rinsing._ 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. + + Water 16 ounces + Potassium chrome alum ½ ounce + +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. + +_Fixing._ After the negatives are developed the particles of 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. + +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. + + +_Acetic Acid Fixing Bath_ + + A + + Hypo 16 ounces + Water to make 64 ounces + + When thoroughly dissolved, add + the following hardening solution: + + Water (about 125° F.) 5 ounces + Sodium sulphite 1 ounce + Acetic acid (28%) 3 ounces + Potassium alum 1 ounce + +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. + +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 +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. + +_Washing._ 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. + +_Drying._ 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. + + +NEGATIVE DEFECTS + +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. + + Exposure Development Result + + Under Under Very thin and weak, only highlights + visible. + Under Normal Thin, shadow detail weak or + lacking. + Under Over Thin shadows, dense highlights, + very contrasty, often fog. + Normal Under Thin, flat, detail throughout but + weak. + Normal Normal Correct density and contrast, + good detail in all parts. + Normal Over Rather dense with too much contrast; + detail may be obscured in highlights. + Over Under Somewhat thin, very flat, full + detail. + Over Normal Rather dense, somewhat flat, + plenty of detail in all parts. + Over Over Very black or nearly opaque, + shadows too heavy, detail lost in + the highlights. + +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 +_intensified_. On the other hand if the negatives have been overexposed +or overdeveloped they should be _reduced_. Formulas for these processes +are given in _Elementary Photographic Chemistry_. + + + + +CHAPTER V + +PRINTING THE PICTURE + + +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. + + +PRINTING PAPERS + +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. + +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. + +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 _single_ and _double +weight_, 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. + +Emulsions are usually coated on a white or buff stock though +occasionally on a cream or ivory base. Printing papers are made in +many _surfaces_—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. + +_Contrast._ 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 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: + + No. 1.—A very soft paper used when printing from contrasty + negatives, or when soft effects are wanted. + + No. 2.—A medium contrast paper used for average negatives. + Portrait papers are of about this contrast. + + No. 3.—A more contrasty paper desirable for weak, thin + negatives. + + 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. + +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. + + +PRINTING PROCESS + +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. + +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.[8] + +[Footnote 8: See Snodgrass: _The Science and Practice of Photographic +Printing_.] + +DEVELOPMENT. The function of the developer and the chemistry of +development are the same as for negatives and need not be repeated. A +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. + +The _formula_ recommended by the manufacturer should always be used. A +specimen formula (Velox) is given: + + Water (about 125° F.) 8 ounces + Elon 22 grains + Sodium sulphite (powdered) ¾ ounce + Hydroquinone 87 grains + Sodium carbonate (powdered) 1 ounce + 55 grains + Potassium bromide 13 grains + Water to make 16 ounces + +For use, take Stock Solution 1 part, water 1 part. Develop 45 seconds +at 70° F. + +If placed in bottles filled to the neck and tightly corked it will keep +for several weeks. + +_Method of Development._ 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. + +After the exposure is made, the tray containing the _developer_ is +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. + +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. + +The print when placed in the _short stop bath_ 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. _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._ + +FIXATION. The prints should be fixed in 15 minutes. A long immersion +may cause bleaching, or discoloration if the bath is too 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. + +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. + +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. + +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 place them between heavy lintless cardboards under a few pounds +pressure until dry again. + + +ENLARGING + +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. + +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. + + +TONING[9] + +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. + +[Footnote 9: For more exhaustive information on toning see Snodgrass: +_The Science and Practice of Photographic Printing_. + +_Elementary Photographic Chemistry._ Eastman Kodak Company.] + + +FINISHING THE PICTURE[10] + +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. + +[Footnote 10: See Photo-Miniature No. 188: _The Exhibition Print_.] + +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. + +Nearly all prints are improved by judicious _trimming_. 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. + +If prints are to be _dry mounted_, 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 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. + +After the print is mounted it is often necessary to do some _spotting_. +Any small white spots are filled up using a No. 1 sable brush and a +card of spotting colors. + +Many prints are made more effective by _hand coloring_. Tinting with +water colors is perhaps the most popular method, although studio work +is often done with oil or pastel colors. + + + + +CHAPTER VI + +MOTION PICTURES + + +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. + +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. + +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. + + +PRINCIPLE OF MOTION PICTURES + +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. + +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. + +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. + + +PICTURES IN THE HOME + +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. + +To overcome these disadvantages simple motion picture cameras such as +the _Ciné-Kodak_ (Figure 9) are now made which use only a narrow width +safety film, 16 mm. (⅝ inch) wide. Some 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. + +[Illustration: Fig. 9] + +Four hundred feet of this film gives the same period of projection when +used in the _Kodascope_ (Figure 10) 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. + +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 thousands +of feet of professionally made pictures have been leased for use +to the Kodascope Libraries, Inc.[11] 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. + +[Footnote 11: At 35 West 42nd Street, New York City.] + +[Illustration: Fig. 10] + + + + +CHAPTER VII + +SCOPE OF PHOTOGRAPHY + + +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. + +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. + +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 _business_ 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 _scientific investigation_.[12] +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. + +[Footnote 12: See _Photography as a Scientific Implement_, published by +D. Van Nostrand Company.] + +And then there is the widespread use of pictures in the magazines +and papers both as _illustrations_ and _advertisements_. 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. + +_Color Photography_ 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. + +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 +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. + +_Color printing processes_ 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. + +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? + + +*** END OF THE PROJECT GUTENBERG EBOOK 77383 *** |