Thread: First telescope
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Old 09-10-2010, 04:00 PM
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Scorpius51 (John)
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Join Date: Sep 2009
Location: Canberra
Posts: 393
Hi again Jared

I got it this time. Personally, I would stay away from claims like this:

"High End Professional Telescope Diameter 114/1000mm 750

Two Barlow lens 2x 3x Unique on ebay magnification 750"


It is absurd to claim that a 114mm aperture will give you a usable x750 magnification!!!!! You would need a much much bigger aperture to get that. The eyepiece(s) and Barlows supplied would probably be of very inferior quality, too.

While the 'scope and mount might be worth $165 as a "Buy it Now" item, you are still better off spending atl east $300-$500 and get a 'scope with better optics and a few good quality Plossl eyepieces into the bargain.

Again, don't forget the binoculars. A good quality pair will be much better value than a low quality 114mm Newtonian 'scope on a flimsy mount - and much more portable and easy to use.

Yes, for a given eyepiece, a longer focal length gives you higher magnification. BUT, if the 'scope has only a limited aperture, then the magnification is useless. That 114mm 'scope will probably have a useful mag of ~x200, at best! At higher mags you are limited by aperture and atmosheric turbulence.

Yes, it is harder to find objects visually with high mags - you would usually start at low mag, then work up higher. It's not too bad if you have a well aligned finder 'scope.

Cheers
John
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