I just bought a 210mm Apo Sironar S in a Sinar DB lensboard. Am I correct that I can simply unscrew it and install the cells in a Copal 1 shutter that I have on hand? No shims or anything else required?
Thanks much!
I just bought a 210mm Apo Sironar S in a Sinar DB lensboard. Am I correct that I can simply unscrew it and install the cells in a Copal 1 shutter that I have on hand? No shims or anything else required?
Thanks much!
The proper aperture scales and maybe shims.
Bob,
I understand the aperture scale, which I have, but can you please explain "maybe shims"? If I need to shim it, will it be obvious if I try the lens or is it a subtle difference that requires test equipment?
Originally Posted by Bob Salomon - HP Marketing
Shims could be needed both for the cells and for the DB board, or one of them - or none. And another shim could be needed for your new shutter.
Ideally, all needed shims will be already installed on the DB mounted lens or ship with your new shutter - but sometimes they are missing, or they replaced two shims (where you'd only need the one belonging to the lens, as you do away with the board) with a single one of the added up strength. To make matters worse, in this ebay age, the whole thing may have been assembled from non-matching parts by the seller. So you'd be well advised to control the spacing of the lens in the new shutter with precision calipers, and shim accordingly (or replace the wrong shims) if there is any significant deviation from the nominal value (respectively the spacing you measured while it still was on the DB board, if that wasn't already flawed).
With a reasonably modern lens, that check for proper cell spacing will usually be sufficient - all camera and lens makers whose products I've handled specified nothing beyond that as a in-store assembly check. If the lens should be a weak performer nonetheless, you might to have to bring or ship it to some dedicated lens service workshop where it can be properly collimated and shimmed to match the new shutter.
I see now that it may not be quite as simple as I thought. I did do some further research—this issue has been addressed on this forum before. I bought the lens from a photographer who used it extensively in his studio and I'm confident that it is currently mounted correctly. I'll mount it in its new shutter and see what I can do—if necessary I'll send it off to the experts.
If there is a shim in front of the DB mount you have also to install it on the front of the shutter if there is one on the back side of the DB mount you have also to put it back on the shutter.
If there is none then its lost or it was not needed!
Cheers Armin
Thanks Armin—you make it sound so simple and easy. Although, I'm always nervous when things are simple and easy...they often seem to turn out not to be.
I'll be receiving the lens early next week and will report back with my adventures.
Richard,
Your DB lens was most likely factory mounted. Take it apart carefully and see if there are shims present. Just make sure you put the cells and shims if any into the shutter in the same way that you took them out of the DB mount.
I have done it. There was a single shim in the front cell. I tested images from both DB and Copal and they were identical. Calliper readings were also identical.
BTW great way to buy great glass for less $...
Grant
I received the lens yesterday and this is exactly what I found—1 spacer on the front and none on the back. I reassembled the lens in the Copal shutter with the shim and checked it on the ground glass using maximum movements to get as close to the edge of the image circle as i could and it looked great. I'll shoot a couple sheets of film today to double check, but I expect them to be perfect. Turns out this couldn't have been easier, and I saved an almost embarrassing amount of money.
Richard,
I have that same lens. It is a cut above the rest. You won't be disappointed.
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