A variation of transillumination used to photograph subjects that are clear or nearly clear. Very useful to visualize faint filamentous fungal hyphae on clear agar. Lights are positioned below and to the side of the specimen which sits on a sheet of clear glass. Below all this put a sheet of black background material, velvet works well. As light passes through the specimen it is bent differentially depending on the index of refraction of the subject, thus allowing otherwise clear objects to glow against a black background. The position of the camera, specimen, and lights must be adjusted for each specimen to obtain the best results.