Calculating date on a Heliar

[cdholden]

I have an old Heliar I am contemplating on selling (once my Universal arrives). To find a date, I need a serial. This one has two six digit numbers on the front rim. Made in Braunschweig, this is an old lens.
Along the top, it has the "Heliar.... DRP 124xxx". Along the bottom half of the front rim, it has "No 106xxx".
Which one is the serial?

Thanks in advance.
Chris

[cowanw]

German patent 124934
lens date 1911 or 12 or so

[cdholden]

So the number after DRP is the patent number? Am I understanding you correctly in that the 106xxx is the serial?

[Paul Fitzgerald]

Chris,

Heliar #112640 had a birthday of 7 Sept., 1911. That was the date on the bit of newsprint wrapped around the aperture assm. as shim-stock. It's American twins are #64940 and #65338, pre WWI.

[edp]

"DRP" stands for Deutsches Reichspatent.

Just as an aside, why do people so often obfuscate lens serial numbers? It's not like a social security number.

[Tom Sobota]

DRP is an abbreviation of "Deutsches Reich Patent", which means something like "Patent of the German Realm". So yes, it's the patent number. DRPs started to be used in Germany around 1877. I think they are still used.

Tom

[eddie]

Chris,

Heliar #112640 had a birthday of 7 Sept., 1911.

Wow 100 years old and a few days. Happy belated.

[Sevo]

DRP is an abbreviation of "Deutsches Reich Patent", which means something like "Patent of the German Realm". So yes, it's the patent number. DRPs started to be used in Germany around 1877. I think they are still used.


Well, the Reich vanished in 1945, and the use of the old terms followed soon after. It has been Deutsches Bundespatent (DBP) in the West from 1949 on, and with most German patents voided in 1945, DRP on a post war item is mostly a indication of pre-war components being used in the post war materials shortage. The GDR used "DDR Patent" or "WP", but was a bit slower at phasing out pre war parts, some lingered on into the mid 50's. That is, DRP essentially means "before 1950", and often "before 1946".

[cdholden]

Thank you for the clarification.
My apologies for the obfuscation.

[Tom Sobota]

Sevo,

Thanks for the clarification. I had read somewhere that the DRP was still used in Germany.

Tom