[Olivier Lisboa]

Hi, I m new in the 645Z's world.
How can I use my old manual NIKKOR lens on this camera?
Man thanks.
Olivier

[tvdtvdtvd]

Welcome to Pentax Forums.

You're not likely to find an adapter to mount a Nikon lens on a 645. The image circle produced by your Nikkors will be too
small to cover the 645 sensor, resulting in vignetting, a characteristic most people would not want. Thus there is not
enough market demand for such an adapter. In theory, you could make your own adapter as long as you're satisfied
with the heavily vignetted image.

The good news is that second hand 645 lenses are relatively inexpensive so you should have little trouble putting
together a useful setup.

[torashi]

The flange focal distance on P645 is also much, much greater, thus you can only use it as a macro lens, probably in reverse. If the lens has a 58mm filter ring (if not, use step-ups or step-down rings accordingly), the 645 reverse adapter set is the one to get. Small, luminous primes work best.
@gdneil has written a thorough macro guide for the Pentax systems and you can download it for free.

[Robot camera]

If it's one of the Nikkors for the older Bronica S2 6 x 6 SLRs, there's plenty of room for an adaptor and the lens will cover the sensor. But from a quick search, you'll need a focusing helicoid too, as the helicoid was part of the camera. You can get helicoids from Ebay. Here's a link to camera mounts arranged by register distance (or flange focal distance, as torashi calls it above)

[kaseki]

...
@gdneil has written a thorough macro guide for the Pentax systems and you can download it for free.

Is that guide linked here at the forum, or do you otherwise have a link for it?

[torashi]

Is that guide linked here at the forum, or do you otherwise have a link for it?

Search the forums. I can't recall the link atm.

[whwang]

See this: http://www.galerie-photo.com/manuels/nikkor-lenses-for-large-format%20cameras.pdf

I believe these Nikkor lenses can be used on P645. The image circles are large, and many of them have flange focal distances larger than P645's requirements. You have to find the right adapter though.

[kaseki]

Search the forums. I can't recall the link atm.

Found part 1 by old4570 here: Macro Guide Part 1.zip - Google Drive
at this link: Macro Guide ( Part 1 ) - Page 4 - PentaxForums.com

It embeds an .exe file within the .zip file, so I may have to install another Crossover Linux bottle to view it.
Parts 2 and 3 may not have been completed; I haven't found them yet.

I don't know if this is the same author as @gdneil.

Edit: Found a better link hidden in the authors signature file: Macro Guide.pdf - Google Drive
It can be viewed directly within one's browser, and includes at least part of Part 2.

[abruzzi]

See this: http://www.galerie-photo.com/manuels/nikkor-lenses-for-large-format%20cameras.pdf

I believe these Nikkor lenses can be used on P645. The image circles are large, and many of them have flange focal distances larger than P645's requirements. You have to find the right adapter though.

Except that large format lenses like that have no focusing helicoid since they rely on moving the front standard of a large format camera to focus. You’d have to hack up a bellows to focus it (did Pentax make a macro bellows for the 645?)