250 film back 101 . . .

[Les Sarile]

The set up as shown was used by James Edger to takes photos of the space shuttle at lift off, the lens is a 500 to 800. The motor drive is all mechanical operated.

Rocket launches, senior portraits . . . versatile!

 

[AgX]

So if he load the film from a 36 exposure roll he only has 36 exposures right? He can't load multi roll of 36 exp in the back isn't it true?

-) a 36exp. multi-roll would mess up everything: the strip likely would get stuck at the film gate and part of the exposures would fall onto the pre-made leaders.
-) 35exp multi-rolls have not been on the market for decades

Likely you mean standard bulk rolls. Basically those are what these backs are made for.
However the 250 exp. backs take a film length not currently available. One thus must roll-off the respective length from a 30m roll to fill the back. The Praktina back I referred to above takes 17m film. That is a length in the past readily available locallly. If the core would fit, such roll could be put directly into the back.