2.8cm tessar f/8

[dsymes]

I've just received a little 2.8cm Tessar and hope someone will confirm (or correct) my estimate of its vintage. The SN is 2235xxx, and it is coated (red T). My understanding is that it is a fairly early coated lens, either 1937 or 1938?

I'm sure it's been discussed before, but I would appreciate any information on how delicate the coating is for this vintage of lens. Luckily, I see no cleaning marks using a fairly strong magnifier to look at the tiny front and rear surfaces.

Thank you,

dsymes

 

[Bill Jones]

Hi Dsymes,

Dating seems correct and yes it is very early for a red T as pre-war lenses were not normally marked as coated. That being said the serial number date is the date a block of serial numbers were released for production not the date of manufacture. So your lens may have been manufactured after Zeiss started marking the red T on lenses during the wartime. All Zeiss lenses that were factory coated were hard coated. Hard coating was the process Smakula patented.

After the war Leitz (Leica) used soft coating and this led many to believe that early coating was all soft. A factory coated Zeiss lens is much less apt to have cleaning marks since the coating protects the lens from them.

Bill Jones

 

[David Murphy]

I had one of these and it was not coated, and I doubt any of them are. It is interesting to use, but in bright light the lack of coatings is quite evident. It is a lot of fun to play around with however - it was very technologically advanced for its era.

 

[dsymes]

Thanks for your replies Bill and David. I also posted an inquiry on ZICG. The suggestion was made that it may have been coated post-war, either by east-german zeiss or by a third party, either of whom might have engraved the red "T" on the front retaining ring. When viewing the reflection of a desk lamp in the front element with a 50mm lens as magnifier, the reflection from the front surface of the element is slightly bluish, while the reflection from the rear surface the same element is neutral/white. If it is not coated, than someone engraved the red "T" fraudulently at some point. Could have happened that way. As someone with a mostly bald head once said, "is a puzzlement!" In any event, I look forward to having some fun with this on my Contax II.