Re: My note bobh "Greek Wars" (digest 1496}

[P3D Bob Howard <bobh@xxxxxxxxxxxxxxxxxxxx>]

RE: In commenting on Dr. George and Gabriels go around on Realist Format
I stuck in my two cents and tripped in one area when I said "twin
systems don't often sync well and the lenses are matched..."
Of course I intended to say "AREN'T MATCHED". Lenses labeled say 50mm
are rarely such. Leica graded focusing mounts with cams into seven
layers to accommodate the spread of a nominal "50mm" lens. To make it
stickier all 50mm SLR lenses ore "retrofocus" type to clear the mirror
with can alter depth of field formulae also. BobH
(One of the costs of the '50s stereos was selecting MATCHED focal
lengths at some greater expense.
Of course a slide bar stereo with one camera has the perfect matched
lenses, just requires a true still life subject.)


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