No help. There doesn't seem to be any numbers on the DB boards that correlate with anything in the Sinar literature concerning proper DB boards for certain lenses. Is there a measurement or something else that controls this?
If you insist, take a look at http://www.image2output-support.com/...20Mounting.pdf for starters. I will either answer your questions or leaving you scratching your head, but that's the reference that Sinar service used.
Yeah, I didn't think the information I posted would be much help. There have been some threads on this forum regarding moving lens cells from DB mount lens boards into standard Copal shutters. So I would think it depends on the shutter size of the lens you wish to mount into a a DB board. If your lens is mounted in a #1 shutter, then you need a DB board threaded for those lens cells. However, a quick search of eBay leads me to think most sellers of DB boards don't know what size they are selling. One seller on there has a board he identifies as for a #1 from a 210mm Sironar. A couple of other DB boards don't give any measurement of the thread size the lens cells screw into. You would probably need to contact the seller, whether on eBay or wherever, and ask them to measure the approx. size of the threads, then see if the size is right for your lens cells. I would imagine DB mounts are mainly sized to the common modern shutter sizes, #0, #1, #3. Then there is how far your rear cell sticks out the rear of the DB mount and if it will clear the shutter blades. If you can find good pics of a DB mounted lens of the same make and FL the as the one you want to mount (either on eBay or Google Images), you can probably get a reasonable idea on the board you need. I think you have posted a good question; one I haven't seen before. Maybe someone else will come up with a better answer the I've given.
Wow! Erie seems to have posted the real answer, all 214 pages of it. I wondered as it was downloading why it was taking so long. I certainly Bookmarked it for future reference. It leads me to think buying a lens already in DB mount might be the sensible thing to do.
Very good. So, from that information, it is not just the thread size that matters. It is also the length of the mounting "tube" that also matters. Too bad that these mounting tubes don't seem to have numbers on them.
Not just the length, but the offset to the front as well. Typically on longer lenses you'll see one to a few spacers bringing the whole assembly forward to clear the shutter blades. ( with attendant extension for the aperture operating mechanism, of course)
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