Nikon Z on PB-4 Bellows

[Jürgen Pfeiffer]

Lately I was looking for a way to adapt Z cameras to a Nikon PB-4 Bellows unit. I didn't want the extra extension that a FTZ adapter produces, and any Dremel work should be avoided too. Wanted to use the tilt and shift capacity of the PB-4 even with objects in middle distance.
Solution was a combination of Nikon K3 ring, 42mm to 52mm step up ring, and a low profile Z to M42 adapter. This gives focus from infinity to around 1:2 with a 105mm EL-Nikkor.
Unfortunatedly, the adapter combo positions the camera upside down. I didn't want to shorten the threads, so I removed the stopping screw on the bellows unit and so the camera can rotate freely.

If anyone knows of an adapter that has similar low profile (maybe F female bajonet to M42 male screw) please let me know.

[Bent Hjarbo]

Smart setup, I just use a normal adapter when I use my PB4, I also have the 105mm f4 bellows, so have infinity as well.

[Hugh_3170]

Jurgen, I don't know if you have workshop access and capabilities, but it should not be too difficult to take a female F-mount off say an adapter or a wrecked F-mount camera body and to screw it to the M42/Z-mount ring that you already have.  (Alternatively get the 42mm hole in M42/Z-Mount adapter opened up enough to insert the K3 adapter into it and epoxy the two together.  K-Ring sets are great building blocks for making up such adapters.)

Either method will result in the F and Z mounts being put into perfect alignment and your camera will be the right way up on the bellows with out having to modify the bellows itself. 

Total thickness should be less than 10mm rather than the 46.5mm of the FTZ.

*****

The last and least expensive alternative is to make up a washer/spacer ring whose thickness is about a half of one turn of your M42 to 52mm ring - about 0.5mm thick, as the Pentax M42 pitch is 1mm, and then place that between your M42/Z-Mount adapter and your M42 to 52mm rings.  A piece of 0.5mm aluminium sheet would be all you need to cut such a washer/spacer.  You might need to experiment with the thickness of the sheet used to make the washer/spacer until you get the alignment of the camera body and the bellows just right.

[Birna Rørslett]

I have made makeshift F-Z adapters by a stock Z mount glued to a K3. The 'flat' M42-Z adapters are not very robust and wear easily.

M58 adapters fit the Z mount directly if you aim for other coupling methods.

[Jürgen Pfeiffer]

Thank You Hugh and Birna for Your suggestions.
I have now screwed the Z-mount of a surplus dumb F to Z adapter onto the F-bajonet of the bellows unit. Stable and short. If I need a F-mount camera on the bellows (not very probable), I can unscrew the Z-mount.

[Birna Rørslett]

It is worth noting that you do get a shorter an more compact bellows unit + camera - however, you also lost extension designed into the lens heads typically used on the PB-4 or similar devices. Thus you might have to compensate by extending the bellows draw further. An example would be the Bellows-Nikkors 105/4 or 135/4. They would still focus to infinity I'd guess, but will need some draw fore this to happen. Also, they would no longer be able to go to 1:1.

For some third-party lens, which might have too much extension to be useful on a bellows without being reversed, the new setup could be beneficial. You might also be able to utilise some enlarger lense with shorter focal length, say 40-50mm, and have a useful working range with them.