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Message: <blockquote data-quote="Tantien" data-source="post: 3152342" data-attributes="member: 116813">Made this point for a newbie earlier but I'm not confident that this will hold true for this crowd. <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite2" alt=";)" title="Wink    ;)" loading="lazy" data-shortname=";)" />If the EP for an 8x32 is 4mmAnd the EP for an 8x42 is 5.25mmAnd your your max Eye Pupil for your age is about<ul> <li data-xf-list-type="ul">40 years old: 6mm</li> <li data-xf-list-type="ul">50 years old: 5mm</li> <li data-xf-list-type="ul">65 years old: 4mm</li> </ul>Then if you are over 50 years old, the 8x42's 5.25mm EP is wasted because your pupil can't open wide enough to receive the EP. True?So [all other things being equal like glass] an 8x32 will be useful for a 50-65 year old whereas a 8x42 will stop being brighter than an 8x32 after 50. Is this not true or is this logic flawed in some way? Is the light gathering capability of an 8x42 still better even if your eye cannot open to receive the extra light shaft? Or is this something like a light intensity (lumens contained within the EP shaft) is higher for 8x42 vs 8x32? Glenn</blockquote>