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Old 16-09-2010, 10:26 PM
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NorthernLight (Max)
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NorthernLight is offline
 
Join Date: Sep 2008
Location: Auckland, NZ
Posts: 343
The 90x900 on an alt az mount would be my advice as well. An eq-mount is absolutely painful for terrestrial and very counterintuitive for a novice. But given that the refractor is about a 1 meter long with its focuser and dew cap it might be too big for you and you could be better of with the 100mmx500mm. Both will more or less show you the following:
Regarding the planets: donīt expect too much of such a telescope and donīt rely on a computer programm that tells you what you could see through it under optimal atmospheric and light polution conditions. those programmes work with high resolution images taken with completely different scopes and expensive cameras. the size and resolution of jupiter in the 90x900 isnīt like the picture on the top right of this forum page. You will see the moons as tiny dots on its left and right but no red spot and hardly any cloud bands. As for saturn, youīll see a tiny roundish thing with little attachments left and right (the rings are edge on for the next years). Venus is very bright and featureless but you can observe its phases (like the moon). Mars would be slightly bigger than a star and somewhat orange-thats it. The moon and the sun (you need filters for both but NO EYPIECE FILTER for SOLARWATCHING-APERTURE FILTER!). The moon, if you havenīt seen it through a telescope will blow you away and when you read the moon columns in A S&T or learn more about it elsewhere you can have a lot fun discovering and studying things-the different phases of the moon bring (almost) every night a different scenario. The sun spots are picking up as well. I have seen my first recently through my telescope and found them amazing (..I now want a coronado..).
Deepspace wise, it all comes down to where you are in terms of light pollution. If you are far out in the country and know where to look at, youīll defenitely find some great open and globular clusters, a few nebulae and perhaps some dim galaxies.
Terrestrial watching is certainly no problem with it. forget about all comas and aberrations-that is nothing you would notice especially during the day.
But donīt forget to fit some decent eyepieces into your budget, a diagonal and a barlow lens (extends your focal lenght by a factor). Iīd suggest a 2xbarlow, a 10mm, a 20mm and a 30mm eyepiece (plössles). The scope brings about 180x maximum useful magnification (apperture in mmx2). with these eyepieces you get 6 different magnifications (mag=telescope focal length divided by eyepiece focal lenght) from widefield to maximum. But donīt go for the cheapest stuff, rather buy one less-its the eyepiece (or occular) that determines the quality of the image you are viewing (crisp and contrastrich or soft and dim).
Have fun with it and be careful not to get hooked too much!
Cheers
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