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Message: <blockquote data-quote="MacGee" data-source="post: 1271631" data-attributes="member: 44532">Fully corrected, Kevin. However I've just remeasured and come up with different numbers. The Olympus is about the same, at 1.55m. But the Leupold, which I previously measured at 5m or more, this time came in at 3.6m. Whether this is due to variation in my vision, even though corrected, or due to incompetence on my part when I did the original measurement, I can't say for sure, but I tend to lean in the direction of incompetence.The light wasn't good the first time around and this may have affected my perception of the Leupold's sharpness. Its 6x magnification, measured against 8x bins may have made me conclude that its image was out of focus when it was only dim and small. This may have been exacerbated by the porro size illusion, which is more pronounced at closer distances. (It's well-known that porros, with their widely spaced objectives, mislead the brain into seeing the image as smaller than it is. So a porro's image will appear smaller than a roof's, which will appear smaller than a reverse porro's. This is one of those ideas that I find hard to assimilate. The image isn't smaller; it doesn't look smaller; your brain just thinks it looks smaller.)Michael</blockquote>