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.
254. Small objects and similar articles must be reproduced in their natural perspective to preserve their true drawing and show a semblance to their original structure. Consequently, any lens which tends to foreshorten or exaggerate the lines, should not be used.
255. By a long-focus lens, in this connection, is meant a lens of a larger size than would ordinarily be used for the same size plate. For example, where an 8 x 10 plate is used, an 11 x 14 or even a 14 x 17 lens will give better results, for the larger the lens, within reason, the better will be the perspective.
Photographing Stoves And Ranges. Stoves and ranges belong to the class of subjects requiring a long-focus lens. For example, consider the heating stove, which may be quite high or low and squatty. The actual article itself is made with good lines and curves to give it a graceful appearance when set up in the home. This same appearance must be retained in the photograph. By working close to it, which would be the case if a short-focus lens were used, you get distortion of lines and only cover the front of the stove, while with the larger or longer focus lens, you admit more of the object - i. e., you see farther around it - thus producing more natural lines in the picture.
257. With ranges we have another feature to consider, the top of the stove and the stove proper being square (box-shaped) and setting quite low and squatty. In order to show the top of the stove and hold it in true perspective, and at the same time admit to view the design of the base-frame, also the legs supporting the frame, we must work at some distance from the object so as to enable us to see around it, as it were. The depth of the stove, measuring from the point nearest to the camera to the most distant point from the instrument, will, in many cases, exceed three feet. With a short-focus lens the distortion would be enormous, and a larger size lens must be employed if correct drawing is to be preserved.
258. In Illustration No. 57, we have a reproduction from an 11 x 14 plate, made with a 16 x 20 rectilinear lens, which you will observe gives a natural perspective and a pleasing appearance of lines to the stove.
Lighting The Object. Stoves should be lighted with a broad front, subdued light, and as such articles are usually photographed at the foundry, the stock-room is generally selected for the purpose. A corner of a room with windows on the side and front gives ideal conditions under which splendid illumination should be obtained. With these conditions the stove should be located, say, 25 feet from the end of the room and 10 to 15 feet from the side. The camera should be located in the corner of the front of the room, thus viewing the stove or object diagonally across the room. The stove should be placed on a platform, say 6 to 8 inches high, and facing broadside to the front windows. With the camera located in the corner you will have a view of the stove showing the front and one side, all in good light. When such work is made under the regular studio skylight, the arrangement of the object is exactly the same, and the camera is worked from one side (the skylight side) of the room, thus viewing the object diagonally across the room, when both side and front of the stove will receive even illumination.
Height Of Camera. The camera, attached to the ordinary tripod, should be adjusted to a height sufficient to give a good, clear view of the top of the stove, so that you can distinguish the lids clearly, but no more.
Preparing The Stove To Be Photographed. A light canvas background should be used, in order to show the open-work and give a good outline for blocking out purposes. Where the trimmings are nickeled the highly polished parts are very apt to appear spotty. To overcome this, the polished or nickeled parts are dulled with putty. Work the putty up with the hands, if necessary, softening it with linseed oil. When it is soft, but not tacky, roll it over the polished parts, which will give them a uniformly light, dull surface. Should the putty be too sticky when first prepared, mix a little powdered chalk with it, which will place it in good condition for use.
Focusing And Exposure. Focus with the lens wide open and when you have obtained a general focus throughout, stop down until all parts are perfectly sharp. This will require considerable stopping down. This accomplished, make the exposure, giving full time - the color of the object being photographed requiring this. The amount of exposure is governed entirely by the strength of light employed and the size stop used. There being considerable latitude in exposure for this class of work, owing to the color of the object being photographed, it is better to aim at over than under-exposure, for any reasonable amount of over-exposure is very easily controlled in the development of the plate. Usually, with a U. S. 32 stop and fair light conditions, using an ordinary rapid plate, from 2 to 5 minutes exposure will be required.
263. Complete detail is always required; hence the shadows must be fully timed, but with slight over-timing of the high-lights you subdue the contrast and by careful development - for which the Universal Developing Formula given in Volume II is recommended - you will produce good results.