What does "D" mean?

Hi!
Question can looks stupid, but it's been a while it's in my head, and can't find any answers.
I'm not talking about the Zenit-D Д lenses (Helios-44Д), and not about the D regime for shutter (bulb).
I'm talking about the Д that I found on an Industar-51Д and recently on a Industar-52Д 500mm/5 .

That's for now the only time I saw this "D".

as far as I know D stands for M39 mount (and Z M42).

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Originally posted by xya

as far as I know D stands for M39 mount (and Z M42).

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Thanks for answer. But I have never seen a "d" in ZM39 lenses, and industar-51 doesn't have ZM39 mount.

Dear Moxies,

as far as I remember I-51D is recalculated I-51 with higher resolution (27 lines/mm in center instead of 22 lines/mm in standard model). Probably this type was more preferable for aerial-photography or dia-projectors (hence the abbreviation).

best regards
altix

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Originally posted by altix

Dear Moxies,

as far as I remember I-51D is recalculated I-51 with higher resolution (27 lines/mm in center instead of 22 lines/mm in standard model). Probably this type was more preferable for aerial-photography or dia-projectors (hence the abbreviation).

best regards
altix

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Interesting.I didn't think projector lens need better resolution. But the I-52 is a pretty heavy lens, and this version come with several color filter and fixation for large format apparature or AFA type camera. Diaprojector are usualy small compared to KinoProjectors lenses (like all those KP or KO lenses).
Still, Dyakuyu!

Dear Moxies,

Будь ласка! Мені дуже приємно

It is hard to understand why I-51D is called "diaproektornyj". Probably it is just a code-word to distinguish it from the standard model.

There were several models of graphoprojectors in the USSR like "ЭДИ-454", "Лектор-2000", etc. These devices project the transparencies on the screen. "ЭДИ-454" has lens "Industar 51" (without D) in special mount and without the diaphragm. Could be that " D" has nothing to do with dia-projectors at all but I've heard such explanation for this letter.

Cordialement vфtre
altix

Thanks a lot altix! :)

Looks like this Industar-51D was Cine 35mm lens.
Hard to believe, since it's initialy a large format lens.

But in a catalogue, I found this





Looks like my has adapted mount, but adapter looks identical.

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Originally posted by altix
It is hard to understand why I-51D is called "diaproektornyj". Probably it is just a code-word to distinguish it from the standard model.

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Dear altix, interesting idea. But FED 5 series were sold with lens Industar 61 л/д. So there is "D" in name of lens but this is not "diaproektornyj" lens.
I wonder what this "D" means.

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Originally posted by Alfa2
But FED 5 series were sold with lens Industar 61 л/д. So there is "D" in name of lens but this is not "diaproektornyj" lens.
I wonder what this "D" means.

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Industar-61 L/D (Л/Д) was produced on LZOS as standard lens for rangefinder cameras (in Russian "Дальномерная камера"). "D" means "Дальномерная" (rangefinder). The other lens from LZOS was Industar-61 L/Z (Л/З) - lens for SLR cameras (in Russian "Зеркальная камера").

"Л" means "Lytkarino" - Lytkarino Optical Glass Factory (LZOS)

Regards, Alexander

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Originally posted by AlexanderK


Industar-61 L/D (Л/Д) was produced on LZOS as standard lens for rangefinder cameras (in Russian "Дальномерная камера"). "D" means "Дальномерная" (rangefinder).
"Л" means "Lytkarino" - Lytkarino Optical Glass Factory (LZOS)

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I thought I-61 L/D means the radioactive glas they used "Lanthan".

From Wikipedia:
Lanthanum(III) oxide (La2O3) improves the alkali resistance of glass and is used in making special optical glasses, such as infrared-absorbing glass, as well as camera and telescope lenses, because of the high refractive index and low dispersion of rare-earth glasses.

For Lytkarino they just used the factory logo.


EDIT: We all know that I-61LD is a good lens. You have to wonder why Lanthanum glass wasn't used more if it improves the optical results so much. Why isn't it used in the new Jupiter-3plus?

Lenny,
yes, you are right. I have read the both explanation about "Л" on Industar-61, but I didn't find any exact confirmation what the "Л" means. For me are the both explanations correct.

Regards, Alexander

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Originally posted by AlexanderK


Industar-61 L/D (Л/Д) was produced on LZOS as standard lens for rangefinder cameras (in Russian "Дальномерная камера"). "D" means "Дальномерная" (rangefinder). The other lens from LZOS was Industar-61 L/Z (Л/З) - lens for SLR cameras (in Russian "Зеркальная камера").

"Л" means "Lytkarino" - Lytkarino Optical Glass Factory (LZOS)

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Thank you, Alexander, geat explanation
All the time I was wondering why we have (Л/Д) and (Л/З) on Industar 61. Now I know.
Regarding letter "Л" I have heared about "Lanthan" too but "Lytkarino" is good explanation either.

Yes, Lenny, I wonder too why lanthanum was not much used.
Leitz used it for the first series of their 2/50mm Summicron (1953/54)then abandoned it.
Same thing for the first Canon 1,2/50mm, in LTM, FL and FD. And for other lenses of this 1955/60 period. Nikon too.

Strange...

Dear all,

I consider that the real revolution in the optical glass industry was done by Otto Schott and Ernst Abbe. Long time it was believed that the increase of profit from the optical glass production is closely connected with the development of new sorts of glass. However in eighties Japan reduced the number of glasses excluding the glasses that contained toxic and radioactive elements. Their lenses they labeled with the green "nature-friendly" label. It was very clever marketing decision. Soon German and European glass and lens producers did the same trick. Now according to European standards not every sort of glass could be produced and used in the lenses. It is funny, but the modern Schott glass catalog almost completely coincides with the 120 years old Schott catalog.

altix



http://www.ussrphoto.com/UserContent/722016_getImage.jpg

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Originally posted by Jacques M.


Yes, Lenny, I wonder too why lanthanum was not much used.
Leitz used it for the first series of their 2/50mm Summicron (1953/54)then abandoned it.
Same thing for the first Canon 1,2/50mm, in LTM, FL and FD. And for other lenses of this 1955/60 period. Nikon too.

Strange...

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I'm reading about radioactive lenses now, Jacques.
This is interesting:
There is someone who said that the nuclear plant where he worked tried to confiscate his "newer" Leica 35mm f/2 summicron due to its "radioactive contamination".

From
http://www.bnphoto.org/bnphoto/LostSites_MonaghanRadioactive.htm

Thorium is derived commercially from certain monazite sands (e.g., from India). Thorium is radioactive itself, emitting alpha particles. The resulting "daughter" products of that radioactive decay series also produce both alpha and beta particles. Related rare earth such as lanthanum are often produced from the same sources, with monazite being up to 25% lanthanum. This decay process means these thoriated glass lenses can gradually become more radioactive over time, as the more highly radioactive decay products build up in the glass. This result is counterintuitive. You would expect the radioactivity to decrease over time. But after chemically purifying the thorium from its ore sources, the thorium is relatively free of these daughter products. Over time, the thorium decays, and the levels of radioactive daughter by-products builds up. Eventually a more highly radioactive equilibrium will be reached, as in the original radioactive ores. So over the years, your "hot" lenses are likely to get more radioactive rather than less. Surprise!

Lanthanum has two isotopes in its natural form, one of which is weakly radioactive. Another source of rare earths such as lanthanum is cerite, which contains the element cerium. Cheap glasses may have iron salts in them, often yielding the familiar green color of some iron salt contaminated glasses. Cerium is often added to glass to convert iron impurities into colorless compounds, yielding clear glass suitable for optical uses. Unfortunately, the rare earths include some chemically very similar elements as contaminants, many of which are mildly radioactive. The chemistry of lanthanum and its associated rare earths is so closely related that it is readily possible to have radioactive contaminants end up in the desired lanthanum salts used in making optical glasses. The amount of such contaminants could also easily vary from batch to batch, depending on the degree of contamination in the original monazite or other mineral sources being used.

I don't think that the original levels of thorium or lanthanum specified for use in these lenses [e.g., in patent filings] is the cause of their radioactivity. Later lenses of the same exact design and glass formulas, but from later batches with higher serial numbers, do not exhibit any similar degree of radioactivity. Nor do they suffer from yellow discoloration over decades of time. So it isn't the thorium or the lanthanum that causes the problem here. The radioactivity of these early lenses is caused by contaminants in the ingredients (e.g., thorium salts) used to make the early lenses. It is these radioactive contaminants which cause these lenses to be more radioactive than their later (more purified) batches of the same design.

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Originally posted by AlexanderK

Lenny,
yes, you are right. I have read the both explanation about "Л" on Industar-61, but I didn't find any exact confirmation what the "Л" means. For me are the both explanations correct.

Regards, Alexander

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Alexander, do you have an I-61LD from Lytkarino?
According to fotoua.com there are only I-61LD versions made from FED. Could be fotoua is not complete about this lens.
Sovietcams.com is in progress about I-61 and might never be finished.

Lenny,
no, I don't have any Lytkarino I-61. This information I found some time ago on different Internet-sites.
So far as I know I-61 was produced in several modifications on three different factories: FED, LZOS and KMZ.

Regards, Alexander

quote:

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Originally posted by AlexanderK

Lenny,
no, I don't have any Lytkarino I-61. This information I found some time ago on different Internet-sites.
So far as I know I-61 was produced in several modifications on three different factories: FED, LZOS and KMZ.

Regards, Alexander

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That's interesting Alexander. We all know that KMZ outsourced their lens production. But I thought FED never did that, but I'm not so deep into FED.

Still there are thousands of I-61LD made from FED, so this "L" definitely doesn't mean Lytkarino.

Perhaps we could say "made for Fed"?
Nothing shows that these Industars were made by Fed. For example, some early I-26m wear a KMZ logo...
I wonder what was exactly the "status" of Industar in the FSU... An independant militaro-industrial complex, able to produce regular lenses for KMZ (Industar 22, etc) and Fed (Industar 10, 26, 61), as well as much more specialized other ones?

Probably the "L" only means lanthane. It's too what the JLP thinks. OK, it's not a proof!

Jacques.

quote:

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Originally posted by Jacques M.


Perhaps we could say "made for Fed"?
Nothing shows that these Industars were made by Fed. For example, some early I-26m wear a KMZ logo...
I wonder what was exactly the "status" of Industar in the FSU... An independant militaro-industrial complex, able to produce regular lenses for KMZ (Industar 22, etc) and Fed (Industar 10, 26, 61), as well as much more specialized other ones?

Probably the "L" only means lanthane. It's too what the JLP thinks. OK, it's not a proof!

Jacques.

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Were those KMZ I-26M delivered with Fed-2 cams?

KMZ started I-26M in 1955, a preseries was produced in 1957, resolution was 28/14mm. Later in passports 30/14mm is mentioned from FED. That's not better than I-22, I-50 and Jup-8. So I guess KMZ gave this inferior I-26M to FED, which was thought to produce for the domestic market with not so high quality as KMZ with their Zorkis.

To me, the factory logo shows where the lens was produced. If it was ok for KMZ to outsource their lens production and use lenses from other factories for their Zorkis it should not be a problem for FED either. Maybe we can find more information about this in 16 years when the FED archives open to the public, or earlier if Ukraine change their law.