90 Super Angulon won't focus

[Alan Smith]

I just bought a used 90 f/8 Super Angulon, mounted it on lens board and can't ge t it to focus. It's mounted on an older Calumet that is made for wide angle lens es(recessed front). I can crank the focus till the bellows are closed and still can't get anything sharp on the ground glass. Is there something I'm not doing o r should I send the lens back? It's under warranty for 60 days. Thanks to anyone who can help!

[fred_1006]

Alan, Does your camera (you didn't mention which one you are mounting this lens on)offer interchangeable bellows capability. You need to be using a bag bellows. Fred

[Doug Paramore]

Alan: Try this: Take the lens off the camera, go to a white wall, and see if you can focus an image of a lighting fixture or window by moving the lens back and forth near the wall. If you can, the problem is with the bellows not collapsing enough on your camera to allow the lens to focus. Also, with the lens on the camera, focus on something a few inches away. That will extend the lens enough that it should focus if it's going too. Even with the recessed lens board, it is possible that your bellows won't collapse enough to allow the 90mm to focus. Hope this helps.

[Alan Smith]

Doug, I can focus the lens on an object by taking it off the camera and moving it back and forth. With the bellows fully collasped, the end of the lens is 10mm away from the ground glass. I can't focus on anything with it on the camera (near or far).

[Doug Paramore]

Alan: This kind of puzzling...With the 90mm, the lens should be about 3 1/2 inches (give or take a little) from the ground glass at infinity focus, and a little more distant at close focusing range. I just checked my 90mm by focusing the image of a light fixture six feet away on the wall. My rear element is about 3 3/4 inches away from the wall when it focuses the light fixture. See what yours does. It is possible someone swapped a rear element on your lens for one of another focal length (I once discovered this on a used lens.) Let me know what you find out. Doug.

[Alan Smith]

Doug, I just can't get it to focus sharp on anything no matter how far or near. If I try to focus on something 6 feet away, I crank it as far apart as the bellows will extend(12.5 inch rail) and it just starts to focus. I can't focus on anything two or three feet away. I think I will just send it back for a refund. Thanks so much for your help.

[Pete Andrews]

I've just read through this, and it sounds completely baffling. The only thing I can think of is that the lensboard might be stopping the rear section of the lens from screwing fully into the shutter. Check that.

I hate mysteries like this. If you ever find out the answer, post back with it.

[Paul Schilliger]

If this is not a minimum flange to back issue, an other reason could be that the shutter has been exchanged and is not properly calibrated for the lens.

[neil poulsen]

Just musing . . . is this a camera you've used before? If not, could there be a problem with the ground glass? Is there a fresnel attached that may not be properly oriented?

[Alan Smith]

The camera will focus fine with my 135mm lens.

[paul schuster]

I have an older calumet also. it was not the bellows that was in the way of focusing my 90mm schneider angulon. it was those very thick front and rear standard. I had a problem focusing at infinity, did great at closer distances. I used a recessed board to correct my problem. now it will focus at infinity.

good luck!

[Todd Caudle]

Talk about a puzzle! I wonder, since you picked the lens up used, if the previous owner sold you a lens with the correct front glass and the rear section of some other lens. Who knows, maybe he was cleaning his lenses one evening and accidentally swapped the rear elements from two lenses. Just a thought, even though I haven't a clue what effect it would have. If you can find someone on this forum with the same lens, have them measure the rear element and see if it jives with your 90mm. Good luck!

[Alan Smith]

Thanks everyone for your responses to my problem. I contacted the store where I bought the lens and after talking to their tech guy, he said there was definitely something wrong with the lens and they would take care of it. Thanks again.