Rodenstock 90mm f4.5 Grandagon-N MC won’t come off lens board

[ondrejek]

Hi guys,

I have got Rodenstock 90mm f4.5 Grandagon-N MC on a TOYO recessed lens board and would like to mount the lens on a linhof style lens board. The lens has a Copal 1 shutter and I can take off the rear element of the lens. However the retaining ring can only be loosened but does not come off as there is a “ridge” on the rear (see photo).

240940

Would you know how to get the lens off the lensboard?

Thanks for you help

Best regards

Ondrejek

[MartyNL]

Has the whole / complete rear cell unscrewed or only part of it?

The reason I'm asking, is because I can't see any internal threads where the rear cell normally screws into at the back of the shutter?

Which shutter is attached to the lens board?

Maybe some more pic's would help showing the front shutter and the rear cell that's been removed.

[ondrejek]

Only the rear lens element can be unscrewed.

I could also loosen the retaining ring, but the ring would not come off completely because of the ridge.

Here a couple more photos of the rear element and rear lens board.

240941240942

[MartyNL]

Which shutter are the lens cells screwed into?

[MartyNL]

Here is my 180mm Rodenstock in a Prontor shutter.
There seems to be what looks like 2 retaining rings and the rear cell screws directly into the shutter.

[MartyNL]

There feels and looks like a spacer or adapter between the lens and the lensboard. Mines on a Linhof board and I've never had the need to remove it.
Almost all of my lenses are much tighter to the lensboard. Admittedly, I have only a few Rodenstock lenses.

[David Lindquist]

Looked at my 90 mm f/4.5 Sinaron W by Rodenstock which I believe is the same lens.That bit that's in the shutter that prevents removing the retaining ring is part of the rear cell. It should unscrew from the shutter (turn counter-clockwise) and be screwed back in to the rear cell. Try to get it good and snug.

Hoping it's not recalcitrant about coming out of the shutter.

David

[Conrad . Marvin]

I also have this lens and agree with David that the part in your shutter is part of the rear cell. Here is a photo of my rear cell with the shutter adapter part on the cell.240948

[David Lindquist]

I also have this lens and agree with David that the part in your shutter is part of the rear cell. Here is a photo of my rear cell with the shutter adapter part on the cell.240948

Thank you very much for providing the picture.

David