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Message: <blockquote data-quote="Surveyor" data-source="post: 1864266" data-attributes="member: 50720">Brock,I will make a guess or two about your 3D perception.The one not usually associated with the general view but, at least for me, affects both the sweet spot and 3D, is collimation. If you look at a point about 30 m away and have a 64 mm IPD, that is a convergence angle of about 7.5’. The best I remember, the measured collimation on your 7x36 ED2 was 17’ divergent in object space (about 28% of allowable in the high performance range) or about 2.5’ convergent towards the objectives. That would make the total convergence (eye line) approx. 10’, or about 30-35% greater than your naked eyes. I have read somewhere that some binocular entities will collimate this way for the enhanced effect but I personally think it detracts from the sweet spot and resolution. As you mentioned, when you increase convergence, you will increase 3D effect. Of course the opposite also occurs.Of course, you will always have all the other factors that affect perceptions, like curvature, astigmatism, etc.Best</blockquote>