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Message: <blockquote data-quote="brocknroller" data-source="post: 1692259" data-attributes="member: 665">That's very odd. One would expect CA to increase with magnification, particularly in the same series of bins that uses the same EPs and has the same aperture. When I did a side by side comparison of the 8x32, 10x42, and 12x50 SEs, CA increased proportionally.The only difference btwn the two Monarch Xs is the exit pupil size, which is 1mm larger in the 8.5x model, and you wouldn't even notice the difference until light levels were low. Could the 8.5x be a "bad sample"? Look at the FOV specs in 8.5x "X" and "EDG" and the metal rod going down the center of the Monarch, obstructing the open space, and you'll see that there's more difference btwn the two models than ED glass. The 8x42 EDG has a 7.7* TFOV, giving it a 61.6 AFOV. With the Monarch 8.5X, you have only 6.3* TFOV, which gives it a narrower 53.5* AFOV. That will translate to a big difference through the EPs. In the 10x5x model, the FOV specs are similar to the EDG:6.5* FOV/65*AFOV for the EDG; 6.3*FOV/66.5* for the "X". The EDG also has better ER for eyeglass wearers. The Monarch X has a right EP diopter control, which, provided it works smoothly, would be preferably to me. I wish there wasn't that much difference in FOV btwn the 8ishx models of the "X" and EDG, and I wish the Monarch X had a truly open bridge design. But if that were the case, who would pay $1,500 more for the ED glass element in the EDG? <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite1" alt=":)" title="Smile    :)" loading="lazy" data-shortname=":)" /></blockquote>

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