Also, without knowing details of the lens' design it is impossible to know where its principal planes are. We all use the diaphragm's position as an approximation, but it isn't exact or always even close.
In principle one can locate the rear principal plane by focusing the lens on a very distant subject, in which case the rear pp is one focal length from the film plane. Similarly, with the lens reversed, to find where the front pp is. But this assumes actual focal length equals nominal, and this is rarely true. Whence custom RF cams for Linhofs with rangefinders, all those Super Graphic RF cams for lenses of the same nominal focal length, ...
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