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Ed Richards
17-Feb-2008, 17:11
I have a fairly new 90mm f 6.8 Sinaron, mounted on a Linhof recessed board. This afternoon, the board fell out of my Sinar/Linhof adapter and hit the concrete from about 5 feet. The lens cap was on and it looks like the lens board hit the concrete on edge, adsorbing some of the shock. The front element pulled the front of the shutter mostly off. No marks or dents on the front element, only a small abrasion on the rear element mount, all the glass is perfect.

Since I have the aperture scale, can I just buy another Copal 0 shutter, screw in the lens, and attach the aperture scale?

Is there any good want to test the lens to tell if I have done it any harm? What is the probability that I have? I am certainly nervous about it, but there is no good way to test it without a shutter to mount it in.

Any clever way to put a safety retainer on a Linhof board adapter? My Sinar has a clip that keeps the Sinar board from falling. Maybe I can attach a loop on each side of the adapter and put a tiny bungee cord across the top of the Technika board.:-)

Mark Woods
17-Feb-2008, 17:39
Put back on the camera and try focusing with it. If you can, do a shot of a newspaper page, process it and examine the neg. Look for side to side sharpness and if there are any parts out of focus or compromised in some manner. You need not make a print for this, but if you do make a print you can compare it with others you have made. If one of the internal elements shifted, it will affect the lens axis and focus. You may need help, or you may suddenly have a "portrait" lens.

Glenn Thoreson
17-Feb-2008, 18:57
Your lens cells will screw directly into a new shutter of the same size. I have some doubt about shift problems. Tolerances on modern lenses seems pretty close. You will need to just shoot with it to tell, unless you want to send it in for a rather expensive diagnosis. It may be that your shutter is repairable, too. Contact S.K. Grimes or Flutot's Camera Repair before you lay out the money for a new one.

Ed Richards
17-Feb-2008, 19:04
Glenn,

The shutter broke into two pieces, scattering iris blades to the wind. I am betting that fixing that will cost me more than the $200 for a new shutter. I did realize that I have another lens in a copal 0, so I can swap elements and see if the lens is OK before I buy a shutter.

Glenn Thoreson
17-Feb-2008, 19:08
Good luck. I hope it's okay.

Mark Sawyer
17-Feb-2008, 22:09
In many shutters, the interior aperture wheels can be adjusted to open to different sizes even though the aperture setting pin is at the same place. I don't know if the Copal 0 is like that or not, but it might take someone who knows the shutter to set it to the right place, even if you have a factory scale.

Ernest Purdum
18-Feb-2008, 10:20
One check should be looking at the lens between polarizers. If a pattern which rotates with the lens is seen, this indicates that the glass is under strain, a common result of dropping a lens and one which is harmful to image quality.

Ernest Purdum
18-Feb-2008, 10:23
You can do the above one cell at a time before getting a new shutter.

I will loan you a shutter for trial purposes if you like.

Ed Richards
18-Feb-2008, 12:09
Thanks to Ernest and others who have offered to loan me a shutter! I did a swap with another lens that has a copal 0, so I am in good shape for testing.

Ernest - just tried the polarizers - no color bands, fringing, or any other indications of stress. Thanks for the suggestion! (Tried a piece of plastic as a control and got rainbows.) Within the constraint that it is hard to tell what is happening on a wide angle lens, it looks fine from a stress perspective.

Ernest Purdum
19-Feb-2008, 11:27
Ed, Good news! Ernest

Clyde Rogers
19-Feb-2008, 21:36
Glenn,

The shutter broke into two pieces, scattering iris blades to the wind. I am betting that fixing that will cost me more than the $200 for a new shutter. I did realize that I have another lens in a copal 0, so I can swap elements and see if the lens is OK before I buy a shutter.

Hello Ed,

I just had one of these shutters apart last week. If the shutter went into two pieces, you're right, it is beyond reasonable repair. Four screws through the back of the case hold the timing mechanism and front mount, and they must have ripped out. The case is almost certainly bent, and the shutter blades went flying. If the aperture went too, it must've been quite an unlucky drop.

Transplanting the scales should work just fine. If the lens tests out decently, it clearly deserves a new shutter. Good luck!

--clyde

Ed Richards
20-Feb-2008, 09:20
The metal on the back of the case sheared apart. But if that absorbed the shock, then great! Tests shots showed the image as sharp as possible at 8x, which means that the glass is fine. A real testament to Rodenstock engineering - when I saw the lens in pieces, I was sure it was ruined. Now I just need a tiny bungee cord to put across my lensboard adapter to keep things from falling out if the lock is loose.:-)

David Karp
20-Feb-2008, 10:59
Now I just need a tiny bungee cord to put across my lensboard adapter to keep things from falling out if the lock is loose.:-)

Or gaffers tape?

Glad the lens is OK.

Ed Richards
26-Feb-2008, 21:27
Final chapter - got my new Copal 0 from BH, got the aperture scales switched, which is a pain for folks with big fingers because they use tiny screws, and the front lens element will not screw in. I look hard at the new shutter and it is thicker than the old one. Seems it has a spacer ring on the front. Looks like metal, looks like a jam on fit, and no description in the lens x-ray diagram. Finally get bold, attack it with the big screw driver while thinking that this is a really bad idea, and it pops off. Lens now screws together fine, the aperture seems to work fine, and the lens is resurrected. $200 for the shutter beats $600-700 for a new lens, but it was not a fun time.