T3D Re: DOF different on different lenses? (TECH-3D digest 382)

[bobh@xxxxxxxxxxxxxxxxxx]

RE: Bob Maxey..a TELEK lens was the negative equivlent of the 
Plus diopter 'close-up' lenses. These when put on a bellows 
camera with ground glass made a 'telephoto' lens out of the primie 
lens (really longer focal length)..so the name TEL EK  !
 The only reason different lenses have different DOF at a given focal 
lenght and f/stop is choice of acceptable circle AND how non-
symetical lenses affect 'size' of exit pupil as seen at the film plane. 
BobH
(Yes John I think that photo comparison ion Kingslake is related to 
what I have been saying.)
Bob Howard (bobh@xxxxxxxxxxxxxxxxxx)
SEND NO PIX OR PROGRAMS TO LIGHTSIDE!!
 Instead send those to:
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End of TECH-3D Digest 383
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