This section is from the book "Complete Self-Instructing Library Of Practical Photography", by J. B. Schriever. Also available from Amazon: Complete Self-Instructing Library Of Practical Photography.
Kodoid Plates Or Cut Films. Kodoid plates or cut films are used in the regular plate holders in the same manner as glass plates. They are, practically speaking, cut non-curling films, fastened on a card mount or support by retaining clips. As Kodoid plates are very rapid, and orthochromatic, they must be handled only in a safe ruby light to avoid fogging. To load your plate holders with the Kodoid plates proceed according to the directions given in Chapter II (Warm Tones On Gelatin Glossy Paper), paragraphs 92 and 93, for loading glass plates. After the exposure, and when you are ready to develop the negatives, remove the film from the mount by pulling off the retaining clips with a knife blade. Slip the film into the developer, with the face side down (the face is the dull side), keeping it moving to avoid air-bells. As soon as it is thoroughly wet with developer it may be turned face up. The general manipulation during the development is the same as for the handling of roll film.
212. As with roll films, there is danger of the emulsion on Kodoid plates becoming soft, unless all solutions are maintained at a low temperature. After the Kodoid plate is developed, rinse it two or three times and transfer to a saturated solution of common alum for a couple of minutes. Then it can be placed in a plain hypo bath, made up of one ounce of hyposulphite of soda dissolved in four ounces of water, but if possible, employ an acid hypo bath; then it is not necessary to place the film in the alum hardening solution. The process of fixing, washing and drying must be carried on exactly as prescribed in paragraphs 202 to 209 for the fixing, washing and drying of roll and cut films.
Film Pack. The pleasure of making pictures, to those who desire to use a regular plate camera, is often marred by the burden of glass plates which have to be carried. The student may not wish to buy a roll holder attachment which will accommodate roll films, and yet the weight and bulk of plates may deter him from much of the instruction and pleasure he can gain with his camera. Also, there is a distinct advantage in being able to focus on the ground-glass and see each picture before the exposure, which is not practical with the folding film cameras. This problem has been worked out in a very simple and effective manner. The film pack is the solution, and the value of what, to many, has always been the most desirable of photographic instruments, namely, the plate camera, is thereby enormously increased.
214. The film pack consists of twelve flat cut films packed together in a light-proof paper case the size of an ordinary plate holder, with an opening on one side the exact size and shape of the film to be exposed. From the top of this case thirteen black paper tabs protrude, twelve of which are the ends of the black paper lying between each film, and the remaining one, marked "safety cover," being the end of the black paper which protects the entire pack from light. Each of the twelve tabs is numbered, the numbers referring to the different sheets of film to which the tabs are attached.
215. The complete pack weighs less than an ordinary plate holder, although containing material for twelve exposures instead of two. The operation of the film pack is to the last degree simple. There is an inexpensive adapter (see Illustration No. 26 of a Film Pack Adapter) to take the place of the plate holder and a film pack to take the place of the plates. The film pack can be loaded into the adapter
Illustration No. 26 Film Pack.
See Paragraph No. 215
Illustration No. 26a Example of Fogging Caused by Failing to Wind Film Tightly on Spoo.
216. After the picture is focused on the ground-glass, the adapter containing the film pack is inserted in the same manner as the regular plate holder. The label on the face of the pack should be broken previous to inserting it in the adapter. Having placed the adapter in position in the camera, remove the slide and pull out the tab on the film pack marked "safety cover," and film No. 1 is presented for exposure. When the exposure has been made, pull out from the pack the tab marked No. 1, which operation rolls film No. 1 around to the back of the pack, leaving No. 2 presented for exposure. This exposure being made, tab No. 2 is pulled out and film No. 3 is ready. Repeat the operation, removing the exposed films one at a time, as additional exposures are to be made.
217. As each tab is drawn out it must not be left attached to the pack, as it is of no further use. It should be torn off across the metal edge and thrown away. When all the tabs are pulled out and torn off, the pack is exhausted and has been automatically made light-tight by the pulling out of the last tab. The pack may then be taken from the camera in daylight and replaced by a fresh one. With the film pack one can make the whole twelve exposures in as many seconds. If one desires to focus on the ground-glass between each exposure, replace the dark slide and, like a plate holder, the adapter containing the film pack may be safely removed.
218. If you desire to substitute plates for films, you can readily do so, as the adapter and pack may be removed at any time. Plate holder and plate can be substituted for any desired exposure, the film operation being afterward resumed by the insertion of the adapter containing the pack.
219. CAUTION. When pulling out any black tab with one hand press the remaining tabs under your finger or thumb of the other hand. This will prevent the possibility of pulling out of more than one tab at a time.
220. The films used in the film pack do not curl upon development. Like roll films, they are non-halation, and also orthochromatic to a marked degree, being very sensitive to yellow, which makes them very rapid and of special value on dull or "yellow" days. The films are, of course, unbreakable and can be sent through the mail.
221. Another feature of the film pack is, that any number of films can be removed and developed without touching the unexposed films remaining in the pack. To remove one or more films for development, before the entire pack is exposed, proceed as follows: