Kodak 90mm Optar serial No.?

[JimboWalker]

I just got a very nice Kodak 90mm 6.8 Optar , but can not figure out the age. I have done a little research, but not sure. The No. is...G13635N. Thanks!

[Louis Pacilla]

Optar was a trade name used by Graflex for a period however the lens is the same as the 90mm f6.8 WA Raptar manufactured by Wollensak & is a WA Gaussian design . it will be post war and I'd guess it was born sometime in the 50's

[Dan Fromm]

As Lou said, not a Kodak lens, a rebadged Wollensak lens. The relationship between Wollensak lenses' serial numbers and dates of manufacture is a complete mystery. It has been discussed here, much hot air has been blown, but there's never been a satisfactory resolution. However, the tradenames Raptar and Optar were introduced after WW II.