Stereonegatoscope

Stereonegatoscope is a device designed for joint viewing or studying of two images at once and (if there is a stereoscopic effect) for demonstrating their 3D properties. It is a device similar to a print, and consists of two frames or tripods installed at a distance allowing the observer to view both photographs together. In this device, images with the help of lenses are concentrated simultaneously and in parallel in front of the upper stages of the eye, and the eyeballs are charged with separating the image from each light source separately.