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Message: <blockquote data-quote="Matt_RTH" data-source="post: 988850" data-attributes="member: 53715">Robert, I compared a 10x50, 7x50, 7x35, 8x32 and 8x25.Unexpected findings:* All brightnesses were in order of objective lens size except the 7x35 was dimmer than the 8x32.  The 7x35 is a vintage Japanese BK7.* The 8x25 was disproportionately dimmer than the 8x32, surprisingly.  Yet I really enjoy using this particular bin (8x25).Tero, I had done that but the problem is that as you view into the bin, the eyes adapt to the change in brightness (pupil size).  Using the method I describe, the view is a certain distance from the exit pupil of the bin to minimize change in your eye's pupil size.  This makes comparison much more obvious.Matt</blockquote>