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HT Finley
22-Oct-2013, 13:07
I am presently looking at a couple of Speed Graphic lenses and wonder if they are so old as to be uncoated. They are 127mm Ektars in Wollensak shutters. And the shutters are marked Made by Wollensak for Folmer Graflex. A little internet study has these lenses going back to 1941, which is a gray area on lens coatings. I'm kinda leaning toward the thought that they are NOT coated. Any ideas? Thanks.

Mark Sawyer
22-Oct-2013, 13:23
See any colors on the glass surfaces?

Peter Gomena
22-Oct-2013, 13:28
If they were coated, manufacturers emphasized the fact. Kodak put an "L" on the lens for "Lumenized" and Wollensak "WoCoated" their lenses. Look for a conspicuous "L" or "W" marking somewhere on the lens.

IanG
22-Oct-2013, 13:29
Zeiss started coating some top end lenses in 1938, British experiments in coatings pre-date that at TTH (Cooke) and various coating techniques were in use in the UK in the early 1940's but probably not for regular camera lenses, it was part of the UK's military war effort and there was a pooling (sharing) of resources between optical companies. (I have an article about early 1940's coatings in a BJPA).

If your lens was made in 1941 it's not coated, aside from a few Zeiss lenses camera lens coating only came in after WWII. I have seen a coated CZJ 150mm f4.5 Tessar from 1938 and the seller didn't realise (it had the Red T - coating symbol).

Ian

Mark Sampson
22-Oct-2013, 20:10
Well, look for the colored 'shine' of the coating, or the whitish reflections if not. The fact of the Wollensak shutter, rather than a Kodak Supermatic No.2, suggests an early lens. EK began coating lenses during the war; 127s made pre-'46 are liklely to be uncoated. They didn't always use the L-in-a-circle to indicate lens coatings, either. Coated or not, a nice sharp lens.

JohnJ
23-Oct-2013, 03:03
As mentioned above, Kodak advertised coatings.

"L"=Luminized (coated).
No "L"= not coated.

IanG
23-Oct-2013, 04:25
As mentioned above, Kodak advertised coatings.

"L"=Luminized (coated).
No "L"= not coated.


I have a coated 203mm f7.7 Ektar and there's no markings to indicate it's coated, I had another I sold last year again no marking, that may be because they were made in the UK though. While both were coated the later one in a Prontor SVS had much heavier and better coatings (the early one was in an Epsilon).

My own 127mm Ektar is in a Flash Supermatic shutter and it looks uncoated so like Mark I think the lenses in Wollensak shutters are much older. My 1945 US Kodak Reference Handbook shows that only a few lenses were Lumenized. The 207mm f7.7 Anastigmat wasn't and it only says the 101mm & 127mm have "treated" air glass surfaces whereas iit states clearly that the projector lenses are "Lumenized".

By 1945 the 127mm Ektar was in the Flash Supermatic shutter but there was an earlier plain Supermatic shutter before that often marked Graphic rather than Kodak when sold with a Graflex Super Graphic. This is another indication the Wollensak shuttered version is much older.

Ian

dave_whatever
23-Oct-2013, 05:42
Ian's right there: Neither of the 203 ektars I've owned had the L, but were coated, both of british origin (the ones that fit into any copal 0 shutter).

jp
23-Oct-2013, 06:33
I've got us-made WWII binocs that are coated, and it's my understanding that it was primarily a military things until after the war. However, Graflex built plenty of cameras during the war, using aluminum, etc... so they may have had access to such means. It'd be a safe bet the lens is uncoated unless you can see it in person to verify the coating. A 3-4 element lens isn't critically needful of coating to do a good job though.

Dan Fromm
23-Oct-2013, 07:25
Well, if people say that they have coated lenses from EKCo made and coated before 1946 I'd be skeptical but wouldn't tell them that the statements are in error.

I just checked on Brian Wallen's site. It appears that Kodak began coating lenses for civilian use in (not at the start of) 1946. In evidence whereof I m'self have an uncoated 101/4.5 Ektar made in 1946.

E. von Hoegh
23-Oct-2013, 07:25
Henry, did you use the 'CAMEROSITY' code to date these?

IanG
23-Oct-2013, 09:03
The article I have in a BJPA gives a few different British Patents regarding early optical coating. From the dates of the Patents it would appear the research work wasn't far behind Zeiss, The British Scientific Instruments Research Association's Patent was filed in 1939. The government controlled the UK photographic industry during the War and coatings would have been important for military optics.

Ian

Mark Sawyer
23-Oct-2013, 09:17
Since British Kodak lenses are also being discussed, it's a good time to point out that while CAMEROSITY was the code in the U.S., Kodak used CUMBERLAND for lenses made in Great Britain.

IanG
23-Oct-2013, 09:33
Mark, I tried checking my 203mm Ektar and 101m Ektar and there's no number.


Well, if people say that they have coated lenses from EKCo made and coated before 1946 I'd be skeptical but wouldn't tell them that the statements are in error.

I just checked on Brian Wallen's site. It appears that Kodak began coating lenses for civilian use in (not at the start of) 1946. In evidence whereof I m'self have an uncoated 101/4.5 Ektar made in 1946.

Well I have a coated 1939/40 US made Dagor but it was coated after WWII and retro coating of lenses was offered in the US.

Your comments about Brian Wallen's site make sense, my Kodak Reference Handbook (1945) implies that many Kodak lenses were now being coated but only mentions Lumenization of two Projection lenses so it was obviously only just being implemented.

I just checked my 127mm Ektar, I'd missed the small L in a circle thinking it was part of the serial number which starts EO so 1946

Ian

EdSawyer
23-Oct-2013, 20:11
All the aero ektars were coated, and date to 1943 or earlier.

David Lindquist
24-Oct-2013, 09:32
Here's what my Kodak Reference Handbook, copyright 1940 and 1943, says about lenses being coated (or as they alternatively say, "treated"):

The six Ektars made for use with the 35 mm Ektra, focal lengths 50 - 153 mm: "Inner air-glass surfaces are coated to reduce reflections…"

The f/2 45 mm Ektar used on the Bantam Special: "Inner air-glass surfaces are treated to reduce internal reflections."

The description of the 100 mm f/3.5 Ektar used on the Medalist refers to "...coating the inner air-glass surfaces of the lens."

For the f/6.3 Eastman Ektars (forerunners of the Commercial Ektars, four lenses 8 to 14 inch focal lenth), this reference says: "...inner air-glass surfaces are treated by a special process which reduces refections…"

The descriptions in this reference for the 105 mm f/3.7, the 101 mm f/4.5 and the 127 mm f/4.7 make no mention of being "coated" or "treated" And likewise for the f/4.5 Kodak Anastigmats, six lenses, 5 - 12 inch focal lengths and the 8 inch f/7.7 Kodak Anatigmat, no mention is made of being "coated" or "treated".

I recall hearing that during this era of coating by Eastman Kodak that the coatings were so soft they were only applied to the internal surfaces. I'd think that in this case it would be hard to tell if any coating was done by a visual inspection.

I don't think this tells us with absolute certainty that no 127 mm (or 105 mm or 101 mm) Ektars were coated until 1946. After all at the time this reference was published Kodak was coating most of its Ektar line and might have begun to do so with these three remaining lenses before the war ended.
David

Dan Fromm
24-Oct-2013, 09:56
David, I have in hand a 101/4.5 Ektar with a 1946 serial number. E0 3946. It is not coated and its trim ring doesn't have the L in circle Lumenized mark. This establishes with certainty that not all 101/4.5 Ektars made in 1946 were coated.

My little lens doesn't establish with certainty that no 101/4.5 Ektars made before it were coated but given the production process I find it hard to believe that any 101/4.5 Ektars made before mine were in fact coated.

David Lindquist
24-Oct-2013, 10:23
David, I have in hand a 101/4.5 Ektar with a 1946 serial number. E0 3946. It is not coated and its trim ring doesn't have the L in circle Lumenized mark. This establishes with certainty that not all 101/4.5 Ektars made in 1946 were coated.

My little lens doesn't establish with certainty that no 101/4.5 Ektars made before it were coated but given the production process I find it hard to believe that any 101/4.5 Ektars made before mine were in fact coated.

I agree with you; I find it hard to believe Kodak would have coated these lenses for a period between 1943 and 1946, stopped for awhile, and then resumed the practice. Also I don't think they put the "circled L" on the lenses they only put internal coatings on. My reference above doesn't use the term "Lumenized" which appears in a later (circa 1952-1962) version I have of the above. I googled Eastman Ektar hoping to find an image to confirm this but didn't immediately turn anything up.

Googling also turned up this obscure reference :) which would have saved me some close reading and typing: http://www.largeformatphotography.info/classic-experts.html
David

IanG
24-Oct-2013, 11:11
So this "Treatment" is quite different to Lumenization which is coating as we know it. Lumenization as a term was in use in 1945. Dan's 1946 lens is listed as "treated" in the 1945 Reference Handbook.

Ian

JohnJ
24-Oct-2013, 12:21
So this "Treatment" is quite different to Lumenization which is coating as we know it. Lumenization as a term was in use in 1945. Dan's 1946 lens is listed as "treated" in the 1945 Reference Handbook.

Ian

The 1948 Kodak Data Book, Kodak Lenses, uses the term 'Luminized' and describes it over about a page.

My 1946 Projection Ektar 4.5/75 (enlarging lens) is 'Luminized', it has a 'L' in a circle and the coatings are obvious. Clearly the term 'Luminized' was being used form at least 1946.

E. von Hoegh
24-Oct-2013, 12:23
I agree with you; I find it hard to believe Kodak would have coated these lenses for a period between 1943 and 1946, stopped for awhile, and then resumed the practice. Also I don't think they put the "circled L" on the lenses they only put internal coatings on. My reference above doesn't use the term "Lumenized" which appears in a later (circa 1952-1962) version I have of the above. I googled Eastman Ektar hoping to find an image to confirm this but didn't immediately turn anything up.

Googling also turned up this obscure reference :) which would have saved me some close reading and typing: http://www.largeformatphotography.info/classic-experts.html
David

Lenses which were made by EKCo for the US military were sometimes coated without the 'L' marking.

Struan Gray
24-Oct-2013, 13:52
Early optical coatings were made from calcium flouride. It is soft, and more easily damaged than the later magnesium fluoride coatings. For commercial lenses, the interior surfaces were often coated and the exposed exterior ones left uncoated because any coating there would get damaged. For military lenses, the exterior surfaces could be coated since the servicemen handling them could be trained how to handle the lens without damaging the coating.

I am not a Kodak expert, but I'm pretty sure the Lumenized name was used for the hard MgF2 coatings once they had become commercially available. I am also pretty sure that some pre-war Ektars were coated with CaF2 on interior surfaces.

Here are some tidbits from two trustworthy old hands on usenet: http://www.pairlist.net/pipermail/largeformat/2002q4/014006.html

The article Michael refers to is probably this one, but I'm too mean to pay for a download to check:
http://www.opticsinfobase.org/josa/abstract.cfm?URI=josa-37-1-1&origin=search

IanG
24-Oct-2013, 16:16
Thanks Struam

My 1945 Reference Handbook says Lumenizing is hard coating with Magnesium Fluoride and any lenses coated this way have the L in a circle symbol. Initially I'd thought my 127mm Ektar was uncoated because I couldn't (and still can't) see any apparent coating despite the Lumenized symbol.

Both UK made 203mm Ektars I've owned have quite different coating with much more distinct colouring but I suspect they were made by Ross under contract and used a different coating techniques. Kodak don't have a history for making high end camera lenses in the UK however Kodak Ltd (UK) were the distributors for a number of years of Ross lenses in some parts of the world like Australia & New Zealand so there were strong links, I guess like EK and Wollensak.

Ian

David Lindquist
25-Oct-2013, 09:26
Thanks Struam

My 1945 Reference Handbook says Lumenizing is hard coating with Magnesium Fluoride and any lenses coated this way have the L in a circle symbol. Initially I'd thought my 127mm Ektar was uncoated because I couldn't (and still can't) see any apparent coating despite the Lumenized symbol.

Both UK made 203mm Ektars I've owned have quite different coating with much more distinct colouring but I suspect they were made by Ross under contract and used a different coating techniques. Kodak don't have a history for making high end camera lenses in the UK however Kodak Ltd (UK) were the distributors for a number of years of Ross lenses in some parts of the world like Australia & New Zealand so there were strong links, I guess like EK and Wollensak.

Ian

Thank you very much Ian for posting this information helping establish a date for the use of "Lumenizing" and the "circled L" symbol.
David