PERCEPTOL is an extra fine grain film developer producing excellent image quality. Designed for use when very fine grain negatives are required but a decrease in film speed is not important. It exploits the superb grain structure of ILFORD medium and slow speed films, DELTA 100 PROFESSIONAL, FP4 Plus and PAN F Plus, and produces significantly finer grain in ILFORD fast films, DELTA 400 PROFESSIONAL, HP5 Plus and DELTA 3200 PROFESSIONAL, compared with a standard fine grain developer.