Dear Vanessa, Sorry to inform you that the lamps are different from one aligned to the other and there are models with lamps from 200-350W. The manual doesn't include info about the lamp power supply. to fugure the optical density you sholud use a calibrated meter or you can try to compare photospeed with that of a known exposure system. most of the optical paths of the lamp houses iv'e seen are very simple. just open and look inside. good luck Shay Kaplan