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.
Paper To Use. Any paper may be employed that will give good, clear, sharp detail - either printing-out or gaslight papers. Where stereoscopic pictures are made on a large scale, usually developing papers are employed, and the cheapest pictures are made where both images are printed on one sheet, while for the best work they may be printed from the original negative in one sheet and cut apart and transposed in the mounting. Usually where gaslight papers are employed for best work the glazed surface papers are used and the single die cut sheets are employed. These die cut sheets are supplied by most all manufacturers of paper.
Stereoscopic Mounts. Stereo mounts are usually-supplied in three sizes, square or round corners, and in a variety of colors - the buff, white and Queen's gray, however, are the most popular. The size of the mounts are usually 3 1/2 x 7, 4x7 and 4 x4 x 7. The size generally used is 3 1/2 x 7. Many large concerns who are making stereoscopic pictures on a cheap scale are using developing papers, cutting their negatives in two, transposing them on a piece of plain glass, masking the negative, and instead of mounting the prints they are printed in one sheet and backed with gelatin backing paper, the backing paper supplying the mount. For instruction for backing prints see Volume IV.
Illustration No. 113