This curious camera was patented by Herman Casler around 1935. It has the form of a box camera and takes images on positive paper (i.e. the paper develops to a positive without an intermediate negative), after exposure the print together with its light-tight envelope is transferred to a separate developing tank for processing.

The print, in its envelope, is placed in the back of the camera, the draw-slide of the envelope is raised by turning a wheel on the back of the camera. The exposure can then be made. After exposure the draw-slide is returned and the envelope removed, the envelope is then placed in the developing tank. A similar procedure raises the draw-slide, the developing chemicals can then be introduced. Unused envelopes can be stored inside the camera. The process was advertised to take five minutes.

Judging by the number of examples that appear few could have been made, most seem to be in very good condition possibly unused. The patent, at 17 pages, is very detailed.

The Science Museum lists the image size as 1 ½" x 1 ½", the patent shows a rectangular image area. This and other examples are marked Model A, No 100. Inside the camera the company name is shown as Photosy Corporation, the same address of 200 Fifth Avenue is shown inside the camera and on the two boxes.