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Binoculars & Spotting Scopes
Spotting Scopes & tripod/heads
Thoughts about first scope
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<blockquote data-quote="jring" data-source="post: 3586592" data-attributes="member: 133897"><p>Hi,</p><p></p><p>you could have done a star test and maybe taken pictures and then either done some reading (online or Harold R. Suiter: Star testing astronomical telescopes) to evaluate it or just asked for help in the reflector forum at cloudynights...</p><p></p><p>The main mirror in a reflector telescope is a quite heavy piece of glass which gets knocked out of position even easier than the usual prisms in refracting spotters - also there is the central obstruction from the secondary mirror which eats up a bit of effective aperture and also limits resolution even in a perfect instrument. </p><p></p><p>The usual problem of how to mount the secondary has been solved by Zeiss with an optical window in front of the tube - elegant but not cheap.</p><p></p><p>Joachim</p></blockquote><p></p>
[QUOTE="jring, post: 3586592, member: 133897"] Hi, you could have done a star test and maybe taken pictures and then either done some reading (online or Harold R. Suiter: Star testing astronomical telescopes) to evaluate it or just asked for help in the reflector forum at cloudynights... The main mirror in a reflector telescope is a quite heavy piece of glass which gets knocked out of position even easier than the usual prisms in refracting spotters - also there is the central obstruction from the secondary mirror which eats up a bit of effective aperture and also limits resolution even in a perfect instrument. The usual problem of how to mount the secondary has been solved by Zeiss with an optical window in front of the tube - elegant but not cheap. Joachim [/QUOTE]
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Binoculars & Spotting Scopes
Spotting Scopes & tripod/heads
Thoughts about first scope
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