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Message: <blockquote data-quote="Pileatus" data-source="post: 3152713" data-attributes="member: 9609">8X32mm exit pupil = 4mm8X42mm exit pupil = 5.25mm32mm objective area = 80442mm objective area = 1385 (72% greater than the 32mm)All else being equal and assuming one can utilize the 5.25mm exit pupil, the 8X42 will deliver considerably more LIGHT to the eye when conditions warrant. We own the 8X32, 8.5X42 and 10X50 SV's and I'm sure you can guess the order of "brightness" in low light! At 63 I can easily see the differences, especially in deeply shadowed areas at dawn or twilight. I visit Alberta in late June each year when daylight fades slowly. When the 32mm starts to give out I get another 90 minutes of useful observation out of the 42mm. This summer I'll have the 50mm and I expect to bird and/or stargaze until dawn.PSThe 32mm SV is my wife's. Also, I've done this comparison with the 8X32 SV and 8X32 SE. Results were similar.</blockquote>