I'm asking for a friend of mine if anyone knows if Pentax 645 lenses can be fitted to a Mamiya 645 ZD body with an adapter? He's been waiting for a 645 digital Pentax but has grown tired of waiting.
Interesting idea, Pentax 645 glass is generally very good. The determining factor is the lens flange to sensor or film plane distance. The receiving camera needs to be shorter to allow for an adapter and still focus to infinity. I've never heard of such a beast, but the Mamiya 645 is approximately 2 7/16"
The lens register of the Pentax 645 is 70.87mm
The Mamiya 645 is 63.30mm, so an adapter should be possible.
The Contax 645 lens register is 64mm. An adapter for Mamiya 645 lenses on the Contax is, however possible (Zoerk makes one). Since the Contax lens mount is so wide, the Mamiya lens mount can fit inside the Contax making an adapter possible.
Sorry for being a slow on this one: sounds like your request might have been directed towards me . . . I did adapt several of my Pentax 645 lenses for the Mamiya, with varying degrees of success.
The 55mm SMC and 150mm f3.5 were both ideal candidates: I tried two methods, both of which worked. The P645 mounting fins are easily removed and with a little patience it's not hard to grind down a donor Mamiya mount to fit. Alternatively, I made some headway with an adaptor solution that combined parts from a Pentax extension tube and a Hasselblad-Mamiya adaptor. Again, with a little patience, a workable conversion can be made without too much trouble.
The dealbreaker for me was the FA35. Though, in my experience, all the Pentax lenses are better than their Mamiya equivalents, the FA35 is in a different class to the M645 unit. However, the rear element sits right out the back of the housing . . . you may recall that early Zörk adaptors actually grazed the element when shifted (ouch!). In order to acquire infinity focus, the FA35 has to be set back into the Mamiya body, close to the point where a minor mirror shave would be necessary. This of course is a much easier proposition with the AFD than the 5D!
I was experimenting with all this concurrently with my temporary ownership of a ZD back. When I returned the back I halted development of the conversion, too.
While all this was going on, I was also investigating the possibility of using a 35mm shift lens with a ZD-size sensor . . . in fact, the performance of the Zeiss PC-Distagon (and even the Olympus 35mm at certain apertures) is very close to the Pentax FA35, and the image circle is of similar size. So if ever I go MF digital (and the advent of the 1Ds III makes this unlikely), I would buy a Mamiya 645 body, shave the mirror, strip the shift mechanism from the Zuiko and use it as a prime.
None of this is rocket science: don't be afraid of having a go, or giving the lens and donor bits to a competent repair guy. Just for the record, Zörk investigated a Pentax-Mamiya adaptor but gave it up: they weren't confident about producing a stable adaptor with such a minor registration difference. Having tried it myself, I still say it could be done, but ideally you need to be prepared to modify the lens a little, too. Good luck!
I want to use my Pentax 645 lens (35mm) on my Mamiya DF. hubsand wrote, that he has experience in making an adapter. Can you or any other one help me with some tips?
Thanks
Cornelius
