Rollei Retro 400S is a high-speed panchromatic black-and-white negative film featuring an extended infrared sensitivity up to 730nm for producing unique halation effects, which can be controlled by exposure. Retro 400S can therefore be used as a normal black-and-white film or as a infrared film when using an infrared filter. Retro 400S is based on the original Agfa Aviphot PAN 400S PE1 black-and-white emulsion.