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diagonal functions


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Hi guys, i am new and have a Northstar day and astro telescope £80 worth, looking at the full moon yesterday with my diagonal and 9mm eyepiece i got a clear view, but when i took away the diagonal which i presume is for day objects on earth there was no image displayed just bright white even after trying to focus, what is happening here as i am under the impression the diagonal is not for astro use, thanks, and how can i improve

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The diagonal is for both day and night use... when you remove it your shoirtening the optical path and so you dont have enought travel on the focusser to achieve focus.

There are various types of diagonal... seeing as its a dual use scope chances are its a prism one which gives you a corrected image when looking through the scope (right way up and right way round)


Edited by Psychobilly
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Hi Heaven 17, a warm welcome to the SGL forum, your diagonal forms part of the focal length of your scope so if you remove it, your scope will be out of focus, unless you put an extension tube in that equals the focal length of your diagonal, HTH.


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Hi Heaven 17 and welcome to the forum.

Blimey your tag takes me back a bit - probably the less said about that the better. :)

Clear skies and put that diagonal back in ASAP as its a clear sky for most of us tonight and there's some observing to be done!


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