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Message: <blockquote data-quote="etc" data-source="post: 1173111" data-attributes="member: 51377">I am confused. I keep hearing different viewpoints. One is that the exit pupil size contributes to brightness, as in 7x42mm. On the other hand, a 7x42mm for example has a lower twilight factor than a 8x42 or 10x42 and certainly less than 10x50. But a 10x50 has a 5mm exit pupil size which is smaller than 6mm of 7x42.Not to mention that a 10x50 has more elements than a 7x42 or 7x, period.So, what factors contribute to brightness, assuming that the coatings are the same in different configurations?</blockquote>