[time-nuts] A real world project need for timing accuracy...
jimlux
jimlux at earthlink.net
Tue Nov 2 13:28:18 UTC 2010
Bob Camp wrote:
> Hi
>
> Ok, I mis-understood the question.
>
> In my experience, you can have big buck (as in many thousands of dollars) optics and not see .2" holes at 800 yards. The bull's eye is a *lot* bigger than the hole the bullet made.
>
>
0.2" at 2400 ft is about 0.08 milliradian.. or 0.3 minutes of arc. Your
eye can resolve about 1 minute of arc... I'm not questioning your
experience, but it seem that even a moderate power scope should allow
you to see the holes. As I recall, the Rayleigh limit for resolution is
something like 0.7 milliradian/mm of aperture, so 10-15 mm aperture
would be in the right ballpark..
I can imagine needing more aperture than 3", though.. you're not
interested in resolving a star, but something more akin to separating dots.
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