Instant film backs for 9x12 cm plate cameras

[Jonathan Ing]

I have just recently discovered the joy of using instant film with a 6x6 medium format camera, and it occurred to me that the 3"x4" instant film packs might be used with a 9x12 cm plate camera (I have collected a few, mostly from the early 20th Century) Thus far, I have been unable to locate a film back specifically for these size cameras, so I was wondering if anyone has heard of such a product, and, if so, where I might obtain one. I'm sure its possible for me to modify another back for such a purpose, but I lack the necessary knowledge and skill to do so on my own. I'd appreciate any information I can get concerning this matter. Thanks.

[FpJohn]

Hello:

I have no direct experience to contribute but I expect that conversions for 4x5 Polaroid 545 film backs would be possible or have been done. Anyone with experience to contribute?

'Best in the New Year to you.

yours
Frank

[Donald Qualls]

Depends to some extent on the camera. I've been looking at my Ziess-Ikon Ideal 250/7 with the idea of making a 4x5 spring back or Graflok converter that would go where the plate holders do, including enough setback to avoid significant vignetting; this would then allow use of 405 and 500/545 Polaroid backs made for 4x5 cameras. I'd probably have to find a 150 mm lens to fit the existing shutters, since it would involve setting the focal plane back around a half inch (with care, I might be able to use the existing infinity stop with the slightly longer lens, but the focus scale would still be off; fortunately, this camera has a second scale pointer without a scale, which would nicely support an alternate scale for this setup).

And that's the major rub -- you're going to have to either reset the infinity stop, or replace the lens with a longer one and then either focus only on the ground glass, or make a new scale (or new RF cam if you're fortunate enough to have an RF-equipped plate camera). Still, might be worth doing if only for the ability to use readily available, light-tight modern film holders and the wider emulsion and processing choices for 4x5...