70mm film back

[H4DGuy]

I obtained a standard 70mm film back for my 500cm. While I am unable to have film processed I continue to do research to find what type of film could be used. It appears that it would not mater if there was perforated or unperforated film. Perhaps someone might know the answer. Thank you

[loceano]

Just stumbled across this.  If you are still out there, maybe this is better late than never.  If not, perhaps it will spur some new info.

I believe the 70mm backs require properly perforated film.  This is unfortunately no longer made.  You should be seeing sprockets on the rollers of the back? 

I read that some 70mm backs were modified by removing the sprockets and allowing non-perforated or 65mm motion picture film (which is available).  Maybe yours was modified?  If so, I read that you should see a rubber o-ring where the sprockets used to be.

I have neither found such a back nor found who would do the modification.  I have one just sitting ready and waiting.

I am looking at motion picture films for other purposes and have found these developing reels (but have not tried them):

    https://ndtsupply.com/ndt-developing-reels.html

I also recently found this hack with Patterson reels for the film:

   https://www.youtube.com/watch?v=5kF8C7Bb0xk

Not sure I'd do it that way permanently - but does give some great ideas for a permanent setup.

Scott