A single-pass schlieren system, utilizing two 14 inch focal length lenses, has been developed for the purpose of demonstrating the feasibility of detecting and recording developer by-product flows from various photographic film/paper-developer combinations. The test samples studied were: Kodak Polycontrast F Paper in Kodak Developer, D-72 and Kodak Kodalith Contact Film in Kodak Developers D-11, Kodalith Super and Kodalith. The apparent amount of detectable flow varied greatly from test sample to test sample, but did not seem to show any significant shift in the pattern due to variations in the exposure conditions on the samples. Differences in the time of initiation of the flows were observed for the various samples. Selected photographs are included