162mm enlarging lensgreenspun.com : LUSENET : Large format photography : One Thread
I salvaged an old 4X5 enlarger from someone's basement, cleaned it up, got it to work, and found that the 162mm Wollensak lens is so long that I have to crank the enl. head all the way up, and then only get a small (less than 8x10) image on the easel when enlarging a 4x5 neg. The head rises at least 33" from lens to easel. This seems unusual, since the 162 is .3x (+/-) the 50mm on my Beseler 23C which, at a lesser same elevation, gives large prints from 35mm negs. Any advice would be appreciated. Thanks Rod
-- Rod Lamkey (rod@LMI.net), July 28, 1998
A quick calculation shows that at 33 inches between lens to easel, a 162mm lens should give you a magnification of x4.17, which is a little larger than 16x20 from a 4x5 neg. But a 324mm lens would give the results you describe.
You should check your lens. You can get a rough estimate of the focal length by holding it up to the sun, and seeing how far away the image falls.
The lens may be missing an element, possibly because otherwise it wouldn't cover 5x4.
-- Alan Gibson (email@example.com), July 28, 1998.
Not knowing what type of enlarger you have I will make a guess as to part of the problem. Is the lens board flat or is it "domed"? The lens may be on the wrong board and that would give the effect of a longer length lens. A friend had an enlarger that had boards of different extension, I'm sorry but I don't recall the brand, to use for the different focal lengths. I beleive the theory was to move the lens away from or towards the condensors, in the same manner that the Beseler head moves the condensor away from the lens. Like I said this is just a guess.
-- Marv Thompson (firstname.lastname@example.org), July 28, 1998.