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.
Introduction. Any picture, no matter of what nature, can be copied, only you must understand, first of all, your instrument, and then the photographic quality of the picture you desire to copy. Different kinds of pictures require different treatment. The successful reproduction of a print depends largely upon the operator. In this lesson we will cover only ordinary work that can be performed with the regulation hand or view camera.
Brief General Instruction.
Apparatus. The ordinary extension hand or view camera used for outdoor work will answer for all ordinary copying. Fixed-focus cameras cannot be used successfully for this work. Cameras fitted with a long bellows are preferable.
Lenses. Single lenses will not do for copying, as they will give distortion and curved lines. A single lens has not a flat field, and as all objects to be copied are usually on a flat surface, you require a lens that will give you a fairly flat field, with a sharply defined image, in which the straight lines of the original are rendered rectilinear and free from distortion. Any ordinary rectilinear lens will do. The shorter the focus, however, the better. With the long focus lens you will require longer bellows, in order to reproduce to the same size. Any lens, which is fitted to a camera with a bellows capacity a little more than twice the focal length of the lens, will answer the purpose.
Copying The Original Size. In order to copy a picture to the size of the original, the distance between the lens and plate must be exactly twice the focal length of the lens. Some lenses of long focus are fitted to cameras the bellows of which are not sufficient to allow of the lenses being used for copying; therefore a lens of shorter focal length would be an advantage. Most modern cameras are supplied with extra long bellows that allow for the extra long focus lens when used in telephoto work, copying, etc.
Illustration No. 6. Copying Apparatus. See Paragraph No. 505.
Copying with Hand or View Camera. 1 77
However, the lack of focal length can be overcome and any-short bellows camera can be used by means of a cone attached either to the front or the rear of the camera, or supplementary lenses may be used which fit over the flange of the regular lens, thus converting it into a short focus lens.
Copying Board. While a regular copying board and a guide upon which to adjust the camera are unnecessary, yet you must exercise care that the camera is placed square to the original. This is essential, otherwise distortion will result. In Illustration No. 6, we have a very simply constructed copying board, made from an ordinary pine-board, 10 inches wide and 4 feet long, with an upright piece, 10 x 14 inches, attached to one end. Upon this end block you arrange the picture to be copied and for convenient focusing the original may be hung upside down. Your camera and picture are attached to the same board and, therefore, are at all times parallel with each other, and when moving the board containing the picture to be copied to and from the light, in order to secure an even illumination, your camera is moved at the same time, so you are always ready for operation.
506. It would be better to have the camera attached to a box or some support which will elevate it above the board, otherwise you may be troubled with reflections from the board into the lens. A block or box about five inches high would overcome all reflection. To each edge of the board should be attached a narrow strip which will serve as a guide for sliding the camera forward or backward while focusing.