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Message: <blockquote data-quote="brocknroller" data-source="post: 1865018" data-attributes="member: 665">Ron,Thanks for that clarification. Seemed odd that bin manufacturers would collimate bins to enhance their 3-D effect if it traded off resolution and edge performance. Does one's IPD affect 3-D perception in bins? I noticed that after I let my neighbor try the EL a couple weeks ago and he handed me the bins, the space between the barrels was almost closed - he has very close set eyes. I couldn't tell what his IPD was from the bins since the EL doesn't have IPD markings, but it was significantly smaller than my 68mm IPD, which is near the top of the upper limit marked on most porros (70mm), though they usually go beyond that limit. For example, the 8x EII is marked from 60mm to 70mm, but goes beyond 80mm on the high end and about 55mm on the low end (henry can chime in with the exact measurements). My point being that there's a wide range of IPD settings. Given this, I wonder if users with small IPDs experience a different 3-D effect through the same bin as users with wider IPDs since changing the IPD changes the distance between the center points of the two objectives? Or is this difference negligible? I was thinking that differences in IPD might explain why some people rave about the 3-D effect in the same bins that others find not as impressive in this regard.</blockquote>