Ars Imago - IMAGO 320 120mm BW Film is a fine grain film with a very high sharpness and wide exposure latitude. This panchromatic film is coated on acetate base and is compatible with most available developers. This black and white film is rated at ISO 320 speed, and can be used both indoor and outdoor in different lighting conditions. The normal sensitivity of the film is 320 ISO, which produces a correct and wide tonal range. With some developments, it can be pushed up to 800 ISO, while the 320 ISO selector is between 200 and 400. You can also set it at 200 ISO and over-expose by half stop.