Miniature Camera Magazine (M.C.M; p634, September 1937) Review of Roll Film Back for Compass Camera

OWNERS of the Compass camera can now replace the normal plate back by a film back in a few seconds, and so small is the space occupied by the new fitting that the total thickness of the camera with the film back is only 1½ in. Special spools are used (an empty one is shown lying by the back, above centre), and the film itself, which is 1½in. wide and 9¼in. long, has a paper leader just under 7in. long, attached to it, and a trailing piece of just over 4in. long. Unlike the larger roll films which have a continuous band of paper from beginning to end the film being attached to it by a gummed strip, the paper is attached to the Compass spool only to the beginning and the end, and thus the rolled up film occupies a smaller space than would otherwise be the case.

When the back is open the new spool is dropped into place, the paper leader pulled out an inch or two and threaded into the slot of the take-up spool. Again differing from the usual procedure, the film is wound with the emulsion side out and in passing from one spool to the other it runs over a pressure plate which during exposure holds the film firmly in position. The holder, however, is so designed that immediately one turns the winding key the pressure plate is drawn back so that there is no friction on the film during winding. A very good point.

There are six pictures to the spool, and one complete revolution of the winding handle (it clicks into place at the end of the revolution) turns on the film for the next picture, so that although the number of the film to be exposed appears in a window there is no need to watch the window carefully to see that the film is turned on exactly the right amount.

After exposure the spools are easily ejected by pressing a button. We developed our test films by the old see-saw method as the total length is so small, and found that the developer did not loosen the paper leader and trailer which acted as convenient " handles." The spools we tested were coated with Selo Fine Grain Pan emulsion, and very satisfactory negatives were obtained.Pan emulsion. The film was developed for six minutes at 65° in Johnsons' Fine Grain Developer. The negatives obtained with this roll film holder are exactly the same size as those
with the Leica, Contax, Retina, Dollina and similar cameras, but are placed transversely on unperforated film l½ in. wide. They thus occupy practically the full width of the film, but there is a good space between them vertically.

The definition of the new lens is extremely good and enlargements of considerable size can be made without any noticeable falling off in sharpness. All our tests were focussed by means of the rangefinder, and we found this to be of high accuracy. The roll film back costs £5, and is immediately interchangeable with the normal plate back. The films costs 1s. 9d. for a packet of two spools (as above, left)
Submitted by Compass Cameras, Ltd., Berners Street, W.1.