Many of you are aware of the code Kodak used to indicate date of manufacture*. It has been suggested that Bausch & Lomb used a similar code in their serial num bers - but the "key" seems to have been lost. Maybe we can reconstruct it. Her e's what I propose: 1. Those of you who have a B&L lens with a coded serial number (2 letters follo wed by some numbers) send me the _complete_ lens info. For example, I have a le ns labeled "Bausch & Lomb Optical Co. - Rochester, N.Y.,U.S.A. - Gold Dot - Mage nta Dot - Protar V. - 90mm E.F. - f/18 - UF3271". The rear element has a matching serial number (only). Pl ease also include any other info that might help us date the lens: if you are th e original owner, when you purchased it; if your lens is still in its' original box, any other labeling info on the box; any sequence info such as "must be afte r x because of ... but can't be after y because of ...", etc., etc. Please also include any pieces of B&L history or "lore" that might shed light on this proble m.
2. I will collect all your submissions for a few weeks and then re-post them h ere and to the rec.photo.equipment.large-format newsgroup (and perhaps also the cryptology newsgroup)
3. Hopefully a pattern will develop that will help us decode at least part of the sequence.
As you'll notice in my example, I included every piece of info on lens with a "-" between parts of the label. I don't know if there will be any changes in the labeling structure that might help us decode the sequence but, just in c ase, please send it all.
Also it has been suggested that, if the lens is in a shutter, we might be able t o use the shutter info tohelp date it so, if yours is in a shutter please also i nclude; shutter type, size, description, serial number.
If the code is like Kodak's, it's fairly simple - two element, direct substitution, with the second element 1-9 or 0 and the first element 4-9 (the co de isn't reported to have started until after WWII --- anybody know otherwise - or when it stopped?). If we're lucky it might be fairly simple -- like if the s erial numbers don't reset to zero each year. Sound like fun?? Please take a second to help. The larger the "example pool" we have, the better our chances of success. Thanks Brian Downey
* The Kodak code is CAMEROSITY where C=1, A=2, etc. (e.g. a lens with a serial number beginning with RA was manufactured in 1952).