testing focal length question

[T3D Grant Campos <gc6094@xxxxxxxxxxxxxxxxxx>]

I'm finally going to be get around to comparing the focal lengths 
of my four lenses (B&L Rapid Rectilinears) before I make the new
stereo camera.  I've decided to make a piece of ground glass to 
fit the old 3A folding Pocket Kodak that the lenses are in, and 
take some measurements.  My questions are:

Will I get accurate results if I leave the shutter in place and 
simply replace the front and rear elements of the B&L Rapid 
rectilinear lenses (there are only two elements)?

In other words, how does the distance between the two elements 
affect the image sharpness and magnification and overall quality?

Does it make sense to do 16 iterations (rear element 1 with front
element 1, rear element 1 with front element 2, etc.)?

If this is not 3D-ish enough could you point me to a website or 
answer me off list?

Sincerely,
Grant Campos


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End of TECH-3D Digest 144
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