Bayonet Suggestions

[ruckusman]

I'm finishing building something based upon the Polaroid 95B for a 6x17 rangefinder and want to use a Rodenstock Sinaron W in Copal 1.

Currently I have this lens/shutter in a re-purposed Mamiya Press mount that attaches quickly to a Linhof board.

This mamiya press mount is too big for the front Standard on the Polaroid 95B so I am toying with the idea of using extension tubes from a Pentacon 6/Kiev 60 and their bayonet mount for the lens onto the Polaroid and a linhof board.

Anyway these parts aren't readily available in Australia, so I though I'd see if anyone has other suggestions before I buy something basically unsuitable.

There may be other medium format alternatives for a bayonet mounting solution that I'm not aware of, so best to ask

[jb7]

How about just getting rid of the bayonet mount entirely,
and attaching the lens directly to the board?
It doesn't take long to re-mount a Copal 1...

[ruckusman]

That's a good point, and it would work fine mounted straight - but the copal 1 shutter doesn't fit cleanly on the polaroid because of the struts that hold the front standard.

So it needs to be extended a little anyways which works to my benefit given the longer focal length of the 150mm over the standard 127mm fitted before

[Ivan J. Eberle]

Any brand of extension tube will have both a male and female bayonet, if you go scrounging for parts to try.

[rdenney]

This mamiya press mount is too big for the front Standard on the Polaroid 95B so I am toying with the idea of using extension tubes from a Pentacon 6/Kiev 60 and their bayonet mount for the lens onto the Polaroid and a linhof board.

It's an old trick to mount barrel lenses on a Kiev 60 body cap and then on the front of a Pentacon Six bellows (and then on a P6 or Kiev 60 camera). A little slicker way to do that without having to use a plastic body cap is to find the Kiev 60 reversing ring. That will have the lens end of the mount on one side, and a 62mm thread on the other. It has minimal length. Then, find a 62mm screw-on cap that is designed for covering the threaded end of a filter stack, or use a 62mm filter coupling and screw in an aftermarket metal body cap. Drill the hold in that for your lens mount.

More rare is the Pentacon reversing ring, which is a couple of inches long and has a 58mm filter thread.

Trevor Allin has put up descriptions of the available tubes and reversing rings here. (http://www.pentaconsix.com/tubes.htm)

The diameter may not be sufficient on these for the rear cell of a wide-angle 150, which I assume you'd need for 6x17. You'll have to make some measurements.

The Kiev 60 tubes were provided as part of the basic kit with Kiev 60's, so they are readily available and should be very cheap.

Rick "who will, one day, mount an iris clamp on the front of a Pentacon bellows" Denney

[ruckusman]

Rick even before I managed to come back and fill in the holes in my original posts you've confirmed exactly what I needed to know

Looking at the 62mm - reversing ring that will be adequate diameter inside to clear the rear cells on the 150 as the slip on lens cap is only 57mm

This may end up being a good solution to a couple of lenses that I front mount onto a Copal 3 also...I'm excited