@D Linquist:
I read with great interest your statement above regarding a lens, Red Dot, with a serial # of 045. Labeled just Apochromat Artar with thr=e customary red dot.
I am looking at another 24 inch, similarly engraved with a serial # of 015!
It is single coated and mounted on an Ilex #5.
Have you found more info on this little mystery since the post above?
First of all I have no doubt that the 24" RDA, s/n 015 that you are looking at is "genuine". BTW that shutter is what I referred to as "new style" or "late style", coming out in the 1970's.
Since this thread was started my notes have grown to include 13 Red Dot Artars with three digit serial numbers. With one exception, s/n 104, the first digit is "0". All are marked on the bezel "Apochromat (red dot) Artar" plus the serial number but no maker. (On edit, to clarify, also included on bezel is focal length and maximum aperture.)
None are marked with a country of origin with three exceptions. These three exceptions were a 30, a 35 and a 42 inch which were marked on the barrel "Made in USA" along with "Schneider Corp. of America." Also an 8 ¼ inch Artar with the serial number 025 had its box marked Schneider Corporation of America. This suggests to me that the three digit serial numbers were a post-acquisition by S.C.A. thing and we can see that three examples were explicitly made in the US.
It looks like each Artar model, i.e. focal length, may have gotten its own three digit serial number sequence as my notes show in addition to the 24 inch lens, s/n 015, a 4 inch Artar, s/n 015.
Also my notes show three Artars marked on the bezel "Schneider (red dot) Artar" but not "Apo" or "Apochromat". Serial numbers are 2000514, 516 and 519. All are marked "Made in Switzerland" and the focal length is 12 inches (not 300 mm!). Ultimately Schneider began making these in Germany and labeled them Apo Artar, serial numbers in the range of 13,xxx,xxx - 14,xxx,xxx. From my Schneider literature it looks like as soon as they acquired the Artar name they dropped their Repro Claron line of dialyte formula process lenses.
Two other things I think worth mentioning: The Goerz Apochromat Artar became the Red Dot Artar in 1953, see my post #10 here:
https://www.largeformatphotography....ferences-on-the-meanings-of-colored-lens-dots The C.P. Goerz American Optical Co. became the Goerz Optical Company, Inc in 1964. Kerry Thalman posted this on this forum in November 2008, based on two pieces of Goerz literature from early and late 1964, one using the former name and one using the latter name.
Finally and once more the "Am. Opt. Co." following "C.P. Goerz" on lenses so marked has and had no connection with the American Optical Company, makers today of sun glasses.
David