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Message: <blockquote data-quote="OPTIC_NUT" data-source="post: 3162393" data-attributes="member: 121951">Here is a major problem with using very high powered binocularsin a terrestrial application:  atmospheric distortions of therays and the image are much stronger looking horizontally than vertically?Add the common haze issue of the lower atmosphere and...what's the point.Other issues with a reflector include contrast, of course. The effect of the diffraction around the supports and secondary reflector. You can actuallyget past this a bit with image processing, but it costs in resolution in the end.Haze, most of the time, actually erases the difference between refractor andfolded reflector.  Horizontally-used, that is.   Not a problem if you lookbetween mountaintops, but that's a pretty rarified bird watching world, outsideof wildlife specials in Alaska or Iceland or following goats on the Matterhorn.Anyway, the great long-ground-distance photos I see from reflector fans aren't any differentfrom the ones from refractor fans.  Over a mile, they are both smoky, so the point is moot.But...a small Cat, short distance?   There is a grey level to it.  I adapted a chunky500mm telephoto to an eyepiece.  It's got great power, esp. with the little barlow swapped in.But taking pictures, I always have to down-sample and re-negotiate saturation and contrast.Obstruction noise happens but, hey....for the price, no CA to see.  It's all about trade-offs.</blockquote>