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Message: <blockquote data-quote="Kevin Purcell" data-source="post: 1386910" data-attributes="member: 68323">Interesting catch, Tero.The "Flip-down objective lens cap" is an interesting oddity. Shade of Brunton though perhaps better implemented.I though the FOVs were a mistake at the start but I don't think so but I suspect they actually are the same.The ISO method gives the correct results ... the older method is an approximation (that works for small FOVs). See the couple of threads where this has already been thrashed out at length <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite2" alt=";)" title="Wink    ;)" loading="lazy" data-shortname=";)" />6.3 degrees = 0.109955743 radiansAccurate (ISO) AFOV is 2 * arctan( mag * tan (FOV/2))i.e FOV = 6.3 degrees = 0.109955743 radiansAFOV(8.5) = 2 * arctan(8.5 * tan(0.109955743 / 2)) = 50.1388164 degreesAFOV(10.5) = 2 * arctan(10.5 * tan(0.109955743 / 2)) = 60.0429364 degreesSo they;re right on the money. So why do the two have the same FOV? Eyepiece design?The 8.5 and 10.5 are interesting examples of more magnification creep. The 8.5x is OK but 10.5. The pseudo open bridge seems more like a marketing gimmick: I'd like that sort of thing to be functional. Perhaps it reduces the weight? Apparently not8.5x is 720 grams = 25.3972526 ounces10.5x is 730 grams = 25.7499922 ouncesI posted on another thread (about the Premier reintroduction, whatever that means!) that Koshkin (from Optics talk) had a look through them and wasn't impressed.One wonders about the price? More than the current Monarchs as they're still in the line up: $400 maybe?</blockquote>

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