Question on Scopes (and other observation devices)

[pmulcahy11b]

Anyone know what the maximum observation range on a scope with a given power and focal length would be I only need one -- I can come up with an algorithm to figure out the rest. (I doesn't necessarily have to be the same range as the weapon; I would guess one could see further than he can hit with a scope.

I'm working on some scopes right now, that's the source of this question.

[StainlessSteelCynic]

Hey Paul, I don't know if this is the sort of technical info you're after but an acquaintance of mine is into astronomy and mentions this site a bit

https://www.telescopeking.com

Specifically this page deals with calculating various factors such as magnification, focal length and so on

http://www.telescopeking.com/guides/telescope-power-calculators/

Yeah it's for astronomy telescopes but I think the concepts are generally the same because as I understand it, maximum effective range is a factor of the image clarity at high magnification - and that all comes down to how good the lenses are, how they're aligned and so on meaning the same magnification on two different company's scopes may actually yield differing effective ranges.

[mpipes]

I seem to recall reading about one mile for a 4x scope, but that may be bogus.