Andy Hewitt wrote:
Jack wrote:

On Celestron's website, I came across the C-65 Spotting Scope which
was cheap to say the least ( less than £100 ) but with the capability
of 30, 60 and 90 power.

I always thought that the more power you wanted, the more you have to
pay ( understandable, considering some of the rubbish on the market ).

Magnifying power is really dependant on the aperture of the scope. As a
general rule, you can use 50x magnification per inch of aperture - to
keep the imaging at a useful level. However, this is really a
terrestrial scope, and not so well suited for astronomy. For a styart
it'll have a correcting prism to make the image upright, this in itself
loses a little light transmission.

So, is this item deliberately aimed at the uninitiated or are the
claims of such a high power genuine?

On this scope, I would say Celestron are probably being quite accurate
at 90x, being within the performance limits of such a scope.
Theoretically it could go to about 140x at its limit, but you probably
wouldn't see much at that power on a small scope. It's also very small
for a Maksutov. I have a 105mm one here, and that is about as small as
I'd want for some reasonable sky watching.

At the moment, I have a huge pair of binoculars I purchased from
Strathspey - they are extremely good at viewing the heavens but being
impossibly heavy, they are not portable and so I can't really take
them where I can get a decent shufty at the night sky ( Death Valley,
California ).

The larger binoculars are better mounted on a tripod.

There's an article on my website about how to make a parallelogram
binocular mount - it's amazing how much more you can see when the
view is rock steady. Useful for family use, too, as the height of the
user
is easily catered for by the parallelogram which keeps the object in view
while being raised/lowered.

--
Graham W http://www.gcw.org.uk/ PGM-FI page updated, Graphics Tutorial
WIMBORNE http://www.wessex-astro.org.uk/ Wessex Astro Society's Website
Dorset UK Info, Meeting Dates, Sites & Maps
Change 'news' to 'sewn' in my Reply address to avoid my spam filter.