When did coating of large format lenses begin?

[tjvitale]

I think I read the coating reference on the Schneider website, maybe in Wikipedia (but then I get a second source). Maybe I did confuse single sputtered coating and multi-coatings. The words are similar. I though it had to do with the size of the chamber used for coating. Certainly multi-coatings were occurring on small format lens even before the war in German lens-makers manufacturers. But it became restricted information, as war related secrets.

Being able to make superior reconnaissance photos was a big war secret.

And the size of the plasma chamber was the limiting fact well late 1950s and 1960s, I was told by a technologist.

This is what I've read.

BTW, if you can poke some other holes in my BHoIT, <http://www.vitaleartconservation.com/BHoIT.pdf>, I'm doing a re-write soon and very few folks have the knowledge to help.

Please try to limit it to items you have proof for, because I'll have to do the research.

ThX

Tim
tjvitale <at> ix <.> netcom <.> com --- for email address remove spaces and carets
510-594-8277

[Bob Salomon]

I think I read the coating reference on the Schneider website, maybe in Wikipedia (but then I get a second source). Maybe I did confuse single sputtered coating and multi-coatings. The words are similar. I though it had to do with the size of the chamber used for coating. Certainly multi-coatings were occurring on small format lens even before the war in German lens-makers manufacturers. But it became restricted information, as war related secrets.

Being able to make superior reconnaissance photos was a big war secret.

And the size of the plasma chamber was the limiting fact well late 1950s and 1960s, I was told by a technologist.

This is what I've read.

BTW, if you can poke some other holes in my BHoIT, <http://www.vitaleartconservation.com/BHoIT.pdf>, I'm doing a re-write soon and very few folks have the knowledge to help.

Please try to limit it to items you have proof for, because I'll have to do the research.

ThX

Tim
tjvitale <at> ix <.> netcom <.> com --- for email address remove spaces and carets
510-594-8277

Pentax introduced multi coating well after the war.

[Oren Grad]

Discussion about coating moved to its own thread.

[Taija71A]

You know that large format lenses were uncoated until the 1980s. Schneider's for sure...

I think I read the coating reference on the Schneider website...

1). No.
2). I don't think so...

As per the Schneider K R E U Z N A C H OPTICS Web Site:
https://www.schneideroptics.com/info...ography.htm#q8

8. When did Schneider begin Multi-coating lenses?

The first Symmar-S lens to be multi-coated was the Symmar-S 150mm, serial number 13,014,862 in March 1977. The 210mm followed and then the rest of the focal lengths were completed by early 1978. The Super-Angulons were multi-coated in the summer of 1978 beginning with the f/5.6 series. The f/8 lenses were multi-coated in late '78- early '79. Apo-Componon HM lenses have been multi-coated since their introduction in 1986.

[goamules]

I think I read the coating reference on the Schneider website, maybe in Wikipedia (but then I get a second source). Maybe I did confuse single sputtered coating and multi-coatings. The words are similar. I though it had to do with the size of the chamber used for coating. Certainly multi-coatings were occurring on small format lens even before the war in German lens-makers manufacturers. But it became restricted information, as war related secrets.

Being able to make superior reconnaissance photos was a big war secret.

And the size of the plasma chamber was the limiting fact well late 1950s and 1960s, I was told by a technologist.

This is what I've read.

BTW, if you can poke some other holes in my BHoIT, <http://www.vitaleartconservation.com/BHoIT.pdf>, I'm doing a re-write soon and very few folks have the knowledge to help.

Please try to limit it to items you have proof for, because I'll have to do the research.

ThX

Tim
tjvitale <at> ix <.> netcom <.> com --- for email address remove spaces and carets
510-594-8277

Tim, I did a quick read of your Brief History of Imaging Technology paper. It has errors in facts, timelines, technologies, I would not submit it anywhere at this point. I suggest you get a few books, like the one by Kingslake, and read what true experts in optical history wrote. Wikipedia, websites, and "technologist" stories are no basis for a history paper.

Back to coatings. In WWII Wollensak coated their binoculars. I'm sure B&L did too, I'm holding a WWII pair that is coated. By the first year after the war, 1946, they were advertising Wocote (coatings) on their Raptar and other large format lenses.

Aug 1946 Popular Photography

[Dan Fromm]

I think I read the coating reference on the Schneider website, maybe in Wikipedia (but then I get a second source). Maybe I did confuse single sputtered coating and multi-coatings. The words are similar. I though it had to do with the size of the chamber used for coating. Certainly multi-coatings were occurring on small format lens even before the war in German lens-makers manufacturers. But it became restricted information, as war related secrets.

Being able to make superior reconnaissance photos was a big war secret.

And the size of the plasma chamber was the limiting fact well late 1950s and 1960s, I was told by a technologist.

This is what I've read.

BTW, if you can poke some other holes in my BHoIT, <http://www.vitaleartconservation.com/BHoIT.pdf>, I'm doing a re-write soon and very few folks have the knowledge to help.

Please try to limit it to items you have proof for, because I'll have to do the research.

ThX

Tim
tjvitale <at> ix <.> netcom <.> com --- for email address remove spaces and carets
510-594-8277

This is not a satisfactory answer. In addition, the bolded text in your response is incorrect if by "multi-coatings" you mean multi-layer coatings in the sense of Schneider's "Multi-Coating."

Here's an assignment for you. Chapter ten of the third edition of S. F. Ray's book Applied Photographic Optics is headed "Thin-layer coatings." One of the references is:

Berthel, F. (1973) The development of anti-reflection coatings for photographic lenses. Indust. Commer. Photographer 13, no. 5, 124. Find it and tell what Berthel said.

Here's another assignment for you:

Get a copy of A Lens Collector’s Vade Mecum. A book originally published on CD ROM, now available as a download from http://www.antiquecameras.net/ Find all of the references in it to coating. It says that TTH started coating in 1944, an assertion that I can somewhat confirm, having had a coated TTH Aviar lens made that year.

Go to www.cameraeccentric.com and look at the catalogs there. You'll find that EKCo and Wollensak started coating lenses for sale to the public in 1946.

I took a look at your www.vitaleartconservation.com/BHoIT.pdf Much in it is incorrect. Politeness prevents further comment.

[Paul Ewins]

The 1950 Schneider german language catalog devotes a full page to explaining their "Duroptan" coating and introducing the inverted red triangle symbol. I've got a contemporary (but different) english language catalog with the following entry:
Schneider "Duroptan" German Patent Nr. 685767
All newly manufactured Schneider lenses are coated. The "RED TRIANGLE" engraved on the lens mount marks the original anti-reflection coming "Duroptan" of Schneider lenses. It is a hard and durable "blooming" and the lenses may be cleaned without fear of damage.

The 1951 Goerz American Optical catalog also says:
Coating of Lenses
We furnish all of our lenses with reflecting surfaces coated. Uncoated lenses can be furnished on special order. Used Goerz lenses coated and adjusted if repairs require their disassembly.

If you follow this link you can see that Kodak's "Lumenized" coatings were being applied to the LF Ektars by 1945: http://www.bnphoto.org/bnphoto/KodakEktarsDB0a.htm

[Jac@stafford.net]

The 1950 Schneider german language catalog devotes a full page to explaining their "Duroptan" coating and introducing the inverted red triangle symbol.

I've seen some Schneiders with a white triangle ▽. Does it have a significant meaning?

[RSalles]

Zeiss in 1939, Kodak in 1940, and after all progressively everywhere,

Cheers,

Renato

[Bill_1856]

The effectiveness of coating was known since the early 20th century, (or maybe even earlier), but the mechanical process of coating was "invented" by Zeiss and Kodak in the mid-1930s. Some pre-war lenses were coated (or Luminized was what Kodak called it), but the process was mainly restricted to coat submarine optics during the war (classified secret), in fact some subs had facilities for coating on-board.