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Message: <blockquote data-quote="tenex" data-source="post: 3653151" data-attributes="member: 135233">I don't think I have much astigmatism, though I am pushing 60 and slightly myopic.  Stars are still nice pinpoints.This odd 6:00 effect occurs at both near and far focus, in bright or dim light.  It's not just field curvature because refocusing can't quite correct it.  Whatever the reason may be for seeing it in the VP 8x25 and not other binos, I think Henry is on the right track, it has to do with the eye looking downward.  I now find that the angle of my head makes a difference: I had naturally been looking down to examine the bottom of the FoV, or tilting my head up along with the bino to view the same target as it approached the lower edge, so I wound up looking down at it.  If instead I tilt only the bino upward, so my eyes are still looking straight ahead (or even up a bit if I also tilt my head forward), the lower edge stays pretty sharp.  Of course this is not what one normally does.</blockquote>