Light source unit assembly for photographic enlarger

摘要

A light source unit assembly for use in a photographic enlarger on the optical axis of its light source between the light source and a negative comprises a first optical system of the semi-diffused illumination type and a second optical system of the diffused illumination type which are incorporated into a unit and alternatively positionable on the optical axis. A diffusing tube housed in a frame is divided into a diffusing chamber for the first optical system and another diffusing chamber having a larger length than the chamber for the second optical system, by a partition having a light diffusing surface on each of its opposite sides. A light passing aperture is opposed to the diffusing surface. A diffusing filter and a condenser are positioned across the path of the light reflected from one of the diffusing surfaces to provide a secondary light source for the semi-diffused illumination system. Another diffusing filter is similarly positioned for the other diffusing surface to provide a secondary light source for the diffused illumination system. One of the two systems is selectively usable on a single enlarger to achieve the desired results.