T3D Re: TECH-3D digest 340

[Jim Crowell <crowell@xxxxxxxxxxxxxxx>]

At 5:24 AM -0700 8/2/98, Norman DAVID Scholefield wrote:
>John,
>
>I was wondering if the fact that the new focus point, using the .25 diopter
>lens, is 27 1/4 feet (8.3M), instead of a focus point of infinity, would be
>a problem?
>

Shouldn't.  When focus isn't perfectly accurate, the amount of blur is
determined by the difference in diopters (1/distance in meters), not the
difference in distance per se.  The difference between infinity (0
diopters) and 8.3 meters is only about 1/8 of a diopter--probably not
detectable.

-Jim C.

-------------------------------------
Jim Crowell
Caltech Division of Biology
Mail Code 216-76
1200 E. California Blvd.
jim@xxxxxxxxxxxxxxx
http://vis.caltech.edu/~jim/Home.html


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End of TECH-3D Digest 341
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