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Message: <blockquote data-quote="Stephen Prower" data-source="post: 3484080" data-attributes="member: 115634">Collimation check of two more CelestronsI've just checked a third Celestron Nature 8x30 Porro that I bought while they were on sale at £33 intending to give it to a friend. Again not collimated. That leaves just a fourth Celestron to check that I have already given away to a relative.The lesson is that a quick check at the shop is not enough. The eyes accommodate to the double image too readily. And they may continue to accommodate in the same way throughout ownership.My wake up call eventually came when I pointed an old Noktovist 8x30 MkII that had performed perfectly well as a house binocular at an aircraft, and a double image of the aircraft appeared that I couldn't get rid of.That lesson luckily only cost me £5. But it came too late for the Celestrons.Stephen</blockquote>