Page "Robot (camera)" Paragraph 6

The camera had other features not specifically related to action photography.

The small optical viewfinder could be rotated 90 degrees to permit pictures to be taken in one direction while the photographer was facing in another.

When the viewfinder was rotated, the scene was viewed through a deep purple filter similar to those used by cinematographers to judge the black and white contrast of an image.

The camera had a built-in deep yellow filter which could be positioned behind the lens.