Voigtlander Apo-Lanthar 150mm f4,5

[Ramon Torres]

I would like to receive information about the Voigtlander Apo-Lanthar 150 mm f4, 5 lens, history, the myth of lanthanum, optical design, image circle, filter thr ead, etc. Thanks in advance, Ramon

[Ed Buffaloe]

There was an article in Shutterbug a few years ago about radioactive rare-earths such as lanthanium in lenses. The Apo-Lanthar is probably the most famous such lens, but some of the early 50mm f/1.4 Pentax Takumars also contained Lanthanium. I tried searching the Shutterbug site for lanthanium and apo-lanthar, but didn't come up with any hits.

[David A. Goldfarb]

I believe the Apo-Lanthar is a Heliar design with the lanthanium element, but I'm not sure of that.

[Michael S. Briggs]

Before and during WWII new glasses were developed with the desirable combination of high-index of refraction and extra-low dispersion, or variation of the refractive index with color. These glasses incorporated rare earths such as Lanthanum and Thorium, frequently in combination. Glasses including Thorium are radioactive. Apparently the Apo-Lanthars were the first large format lenses available to the public to incorporate such glasses. As such they acquired a reputation that continues as a "mystique" and quite high prices. I have strong doubts about whether their quality will exceed that of current lenses. Some current lenses include extra-low dispersion glass, such as the Apo-Sironar S.

[John Hicks]

A couple of years ago Phil Davis mentioned that the school had gotten several Ap o-Lanthars for student use and he found that they weren't any better than the ru n-of-the-mill Nikkors etc. I have no firsthand experience with them myself.

[Steve Pfaff]

I have a Voigtl??nder Apo-Lanthar 150mm f4,5. It's O.K for color, plenty sharp with a sight warming cast. Where it really shines, though, is black and white. It's hard to explain, but it produces a kind of luminescent quality that's very pleasing; even in Polaroid?s. I don't do much black and white anymore, but when I do I always try to use this lens.