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Scott Davis
9-Aug-2022, 08:49
Anyone know what the approximate coverage for a lens like this would be? I've got a line on one that is cheap enough to be worth investigating even if it doesn't have massive coverage (I'm guessing based on focal length alone it should cover 14x17).

Dan Fromm
9-Aug-2022, 09:37
General principles (f/10 process lenses typically cover around 45 degrees) predict that it won't come close to covering 14x17.

ridax
9-Aug-2022, 10:22
Dialyte process lenses don't cover, but this thread: https://www.largeformatphotography.info/forum/showthread.php?154035-Late-Wollensak-Process-Lenses-Designs-and-Specifications suggests the Wollensak is probably a Double Gauss, so it may cover.

The 600mm CZJ Apo-Tessar and the (uncoated) 600mm LOMO Industar-11M would cover, too.

Whir-Click
9-Aug-2022, 14:12
Is this an uncoated lens in a black enamel barrel with Art Deco font? I ask because these pre-war Wollensak process lenses are poorly documented, but many are the same double Protar design as Wollensak’s Series 1a Velostigmat, with correspondingly large coverage.

Once coating was introduced, Wollensak changed process lens designs to the Double Gauss, Dialyte, Plasmat, and others depicted in the handy 1962 catalog in the thread linked above.

If it’s not too expensive, try it out, report your findings, and your experience will benefit us all.

aphcl84
9-Aug-2022, 19:20
With the Apochromatic Raptars forward lettering denotes a double guass design while reverse lettering lenses are dialyte. Regardless neither type will cover 14x17 though they may illuminate it. Earlier types and amatons are less clearly marked.

Scott Davis
10-Aug-2022, 08:35
Is this an uncoated lens in a black enamel barrel with Art Deco font? I ask because these pre-war Wollensak process lenses are poorly documented, but many are the same double Protar design as Wollensak’s Series 1a Velostigmat, with correspondingly large coverage.

Once coating was introduced, Wollensak changed process lens designs to the Double Gauss, Dialyte, Plasmat, and others depicted in the handy 1962 catalog in the thread linked above.

If it’s not too expensive, try it out, report your findings, and your experience will benefit us all.

This was a pre-war uncoated anastigmat in the brass barrel with black enamel. I ended up letting it go because I really didn't NEED it. I would have had to spend money on getting it mounted in a shutter that I should put toward getting my 600 Apo-Germinar put in a shutter.