Hasselblad's film back — the A12 for 6x6 format on V-system cameras.
The Hasselblad A12 Film Back is a removable film magazine for the Hasselblad V-system medium format cameras (500-series), loading 12 exposures of 6x6cm on 120 format roll film. It is one of the most commonly used Hasselblad backs alongside the A16 (16 exposures on 120) and A24 (24 exposures on 220 film).
The A12 magazine holds a 120 film spool and produces 12 square 6x6cm frames per roll. It attaches to any Hasselblad V-system body (500C, 500C/M, 501CM, 503CX, etc.) and can be swapped mid-roll with a darkslide. No electronic coupling is provided — purely mechanical operation.
The A12 is the standard film back for Hasselblad V-system medium format photography and enables mid-roll film changes when using multiple backs — a technique used by professional photographers to switch between film stocks. Darkslide presence is essential for mid-roll back swapping.
Verify that the film counter resets correctly. Test darkslide insertion and removal. Inspect the film pressure plate and film track for scratches. Check the film frame spacing mechanism by loading film and advancing several frames. A back without a darkslide cannot be removed mid-roll without fogging the film.