Mamiya C single exposure attachment film format

Good afternoon to all fellows.

I have recently purchased some NOS single exposure plate holders to fit the single exposure back attachment of the mamiya C twin-lens-reflex. These holders can hold a glass plate or, with the interposition of a tin adapter provided with each holder, a sheet of cut film.

I do not understand, however, which kind of format these are intended for, as standard 6x9 cm film sheets proved too big to fit into the guides. Was a format of sheet cut film smaller than 6x9 cm once available, perhaps?

Did anyone devise a clever modification to the sheet adapter to have it fit standard 6x9 cm sheets, without the need of filing away the metal guides, end rivets and such?

Thank you very much.

IIRC, they fit 2-1/4x3-1/4 sheet film, slightly different size than 6x9, they are cut to fit inside the holder so smaller. Of course, you can always trim the film, which would prove easier than modifying holders.

I use Efke cut film in my Mamiya Press holders. I think they're the same as used in the Mamiya C series.

http://www.freestylephoto.biz/19152...so-50-2.25-x-3.25-inches-25-sheets?cat_id=404

6.5x9 cm sheet film, maybe?

Ah, sorry, now I saw that 6x9 film was too big, so even bigger sized film might not fit, no...

According to the manuals, the inserts for film are: Type J for one-quarter of 4.75" x 6.25" sheet film, Type D for 2.5" x 3.5" (6 x 9cm) sheet film.

You can see pictures of a late version of a single exposure back at http://grahampatterson.home.comcast.net/~grahampatterson/grahamp/mamiyamisc/index.html

Thanks everybody for your informative reply. I think I'm going to file away the guides because it's done once and for all instead of cutting each and every time a film sheet in total darkness. Also, film cut to 2x3'' size won't fit the Combi-Plan tank so it would be a pain to develop.

Have a nice day!