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Hi Sam,
Yup, the 90 x 900 on the AZ3 seems the best mix of size, ease of use, terrestrial capability as well as performance. For $249 its well within the budget, HOWEVER, it seems its out of stock.
On the same page is the Black Diamond version (not ED) but much SEXIER paint job but I think the same visual design and performance. But paying $100 more for the speckly Black Diamond paint job may be a bit silly.
Check with Andrews to see if they can rustle up a 90x 900 AZ3 package even though the site says they dont have any, you never know.
$249 is a great price to get you started. Stay away from EQ mounts if portability is your thing as AZ are a doddle to carry and set up. EQ needs to be roughly polar aligned and thats not much fun if you are starting out on the limited budget you have.
Nothing to do with a refractor on an AZ, simply extend the legs, plonk it down and then off you go, cruising the night sky. You will be surprised at what the scope can pick up.
The 102 x 500 is shorter and has an F5 focal length which means its more widefield (not as narrow view as the 900mm one at F10) BUT the smaller focal length means you cant get up as close to say a planet or smaller Deep sky nebula etc with a shorter focal length. For example, the 900mm scope with a 10mm eyepiece will give you 90X magnification without any sort of barlow magnifying lens. With the 500mm scope, that equates to 50x magnification (FL divided by EP) so therefore the view is close to twice as big as the 500mm one. As a rule of thumb, you will only get about 2-2.5 times the aperture of the scope as the maximum magnification that is usable, so that means the 90 would be about 180x-225x and the 102mm would theoretically give 200x - 250x BUT to get that from the 102mm, you would need a 2mm Eyepiece or a 5x barlow on the 10mm I mentioned before, which is NOT going to work. On the 90mm, the longer Focal length means to get 180x, all you need is a 10mm eyepiece and a 2x barlow (recommended) to get to a pleasing, yet still usable maximum of 180x magnification.
Black Diamond complete "AR" refractor packages!!
90AR-AZ3 A$349
Cheers
Chris
Last edited by Screwdriverone; 17-09-2010 at 12:33 AM.
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