Acquired a No.1 Dallmeyer Rectilinear and am wondering if there is a place where I can convert the wheel stops to f stops? There are 5 stops in addition to the wide open.
To get the speed of the lens would one divide the focal length by the diameter of the front lens or by the diameter of the largest stop as seen through the lens or by the diameter of the largest stop viewed directly (not through lens)?
If the next stop diameter is 1/2 of the previous then the f-stop for that is 1/2 of the previous? Eg. IF 1cm hole works out to f/4, then 0.5 cm hole is f/8?
Aso, is this the wide angle version of the Rapid Rectilinear? And lastly, the wheel is loose (no click stops for the apertures) - any suggestions on how to stabilize it when photographing?
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