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Message: <blockquote data-quote="henry link" data-source="post: 1266413" data-attributes="member: 6806">There's one last boosted magnification test I use which I didn't do to the binoculars at the beginning of this thread.  Boosted magnification tests are tests of performance at full aperture because the exit pupil at high magnification is so small. Of course we seldom use most binoculars in daylight at full aperture so I stop down the test binoculars to simulate performance in daylight. If I want to be very thorough I may use several stopdowns, or if i'm lazy a single measurement at a 3mm exit pupil. That means stopping down every 8x binocular to 24mm. Some aberrations and defects will show considerable improvement when the binocular is stopped down. Chromatic and spherical aberrations are reduced. Astigmatism and pinching may disappear, but miscollimation will remain. Typically the boosted magnification image looks cleaner but dimmer than full aperture. The true resolution measurement usually suffers simply because it can't be any better than a 24mm aperture will allow. This test gives a more detailed look at how the optic is actually performing in a normal magnification resolution test in bright light and is a pretty good indicator of how good normal daylight performance really is.Thanks all for an interesting discussion. Unless somebody has a question for me or something completely new is introduced I think I'll move on now and leave this thread to others.Henry</blockquote>

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