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View Full Version : Holy APO Lanthar, are you seeing what I'm seeing



Vick Ko
20-May-2008, 13:05
Holy APO Lanthar, are you seeing what I'm seeing on the *bay - $1512 for a 150/4.5 APO Lanthar?

Okay, granted it is a Linhof lens.

But seems like that is setting a new high for this lens.

...Vick

Vick Ko
20-May-2008, 13:12
Oh, and it needs a shutter service.

Vick

Dan Fromm
20-May-2008, 13:29
Vick, live by the cult, die by the cult. What a shame that we can't anticipate new cults before they arise and accumulate soon-to-be-highly-valuable cult objects.

Ole Tjugen
20-May-2008, 13:29
From this side of the ocean it looks like a pretty ordinary price - it's just that the dollar has lost value. Around $1200 last year is about $1500 now, in Euros.

goodfood
20-May-2008, 22:53
Another Apo Lanthar go to China.

tom north
21-May-2008, 11:58
I seem to recall that Lanthar glass is radioactive. Does anyone else remember reading about this?

Jiri Vasina
21-May-2008, 12:25
Tom, yes, it's said Lanthar lens has it's name because it contains Lanthanum - one of the rare earth elements that is radioactive. From what I recall it should be better at correcting some of the optical aberations. The amount of radioactivity in the lens is by any means negligible - you are recommended not to sleep with the lens under your pillow (or between your legs :) ) but in any other possible use it will do you no harm.

Ole Tjugen
21-May-2008, 13:43
Tom, yes, it's said Lanthar lens has it's name because it contains Lanthanum - one of the rare earth elements that is radioactive. ...

Ehr - no.

Pure Lanthanum is not radioactive - but it tends to contain quite a lot of Thorium, which is.

The rest is correct: Lanthar lenses contain Lanthanum glass, which is radioactive, and has a very high refractive index combined with a very low dispersion (or is it the other way around?)

The radioactivity is negligible - unless you have a habit of eating your lenses, keeping it in your trouser pocket, or sleeping with it under your pillow. ;)

Steve Hamley
21-May-2008, 18:18
Not all Apo Lanthars are radioactive. They replaced the thorium-containing glass later on with glass that did not contain it. Thorium was added to increase the index of refraction, and later they didn't need it. I have a 150mm Apo Lanthar that shows no radioactivity above background, with the possible exception of trace thorium present in many optical glasses.

http://www.orau.org/ptp/collection/consumer%20products/cameralens.htm

Steve

Jiri Vasina
21-May-2008, 22:41
Ehr - no.

Pure Lanthanum is not radioactive - but it tends to contain quite a lot of Thorium, which is.

The rest is correct: Lanthar lenses contain Lanthanum glass, which is radioactive, and has a very high refractive index combined with a very low dispersion (or is it the other way around?)

The radioactivity is negligible - unless you have a habit of eating your lenses, keeping it in your trouser pocket, or sleeping with it under your pillow. ;)

Thanks for the correction. Late in the evening the thinking is more clouded than other times. :)