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Rare 645 back for Hasselblad

Vlad Drakula

New Member
Hi everyone, I’m new to Hasselblad cameras. I’ve got recently a 500cm body with a kinda strange back. The back has indicator 16 on the side where the crank is and also there is letter M. What’s interesting that the 645 frame is not centred according to the square frame of a back. Unfortunately I’ve already loaded the film in the camera and took few shots, so I can’t open the back and take a picture and tell the position of the 645 frame according to a square frame, but I drew two possible variations. My question is if I want to make a paper mask on the viewfinder for this 645 back, where should be the wide strip of the paper in the viewfinder, at the top or at the bottom?


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New Member
To find the answer, you will have to pull the protective slide out and make a picture of the filmframe (do it fast in subbed light to avoid some occasional flare), you will only lose one of the sixteen frames, but I think it's worth the sacrifice.
I couldn't find an answer in Ernest Wildi's 'The Hasselblad Manual' book, this makes me very curious!


New Member
Try bringing the mag into a darkroom (or a changing bag) - pull out the slide and try by feel with your finger to determine where the hole is.


New Member
It must be landscape to get the extra frames and in the middle of the frame to avoid edge of lens issues.
The great thing about the P45 digital back on the V system is one could swap from landscape to portrait by revolving the back.
Unless you want to shoot everything landscape I’d flog that back to someone who does and get an A12 back then crop any way you want.
Happy cropping.