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Gene McCluney
18-Feb-2007, 11:12
I have a 16 inch late model Rapid Rectilinear, with iris diaphram. Possibly updated by B&J, because it is coated in black barrel. I am wondering about the covering power of Rapid Rectilinear lenses in general. Would this cover 11x14? What can I expect from this for b/w photography stopped down?

Glenn Thoreson
18-Feb-2007, 14:16
I going out on a limb and saying yes, with moderate movements. Based on my experience with shorter focal lengths. RR is extremely sharp in the center, falling off as you reach the edges. Best used at small apertures. I love the look these things provide. My opinion - mount it up and shoot a couple. See what you think. It's all subjective, you know.

Ole Tjugen
19-Feb-2007, 01:26
It all depends on the RR you have, and your definition of "coverage".

By my literature from 1910, confirmed by my own experience, a Rapid Rectilinear (or rather, an Aplanat which is what's mentioned in my books - and most of mine are Aplanats) was sharper in the central 30 degrees than even the best contemporary Anastigmats. Sharpness then drops off - partly due to field curvature, partly from aberrations - until it goes to total mush at about 70 degrees. But there are very many small variations of the construction, including narrow-field portrait lenses and very wide-angled lenses. So the best way to determine coverage is to try it yourself.