I have a Sanderson Whole Plate, which was built about 1905. This has a rear box of 11 1/2 inches by 10 inches. It has sides 1/8 inch thick, and the ornate top is 1 inch, and the bottom 3/4 inch. The rabbetted size is 9 3/4 inches square, and is 1/8 inch deep. This mahogany and brass camera was made for book form darkslides using plates, although when I bought it in 1969 it came with film inserts in the darkslides. I have always used film with the darkslides, although plates were available when I bought the camera. The register is slightly different for the film held in an insert, when compared with a plate, and I had to alter the position of the ground glass screen accordingly. With the film insert the distance from film to edge of darkslide is 7·2mm (0·283 inches), and the distance from the emulsion surface of a plate to the edge of the darkslide is 6·5mm (0·256 inches).
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