newbie aperture question

At 30x with a 18mm EP that means that the focal length is 540mm with a 150mm
aperture or about F3.5. This is a scope which is more usable for the larger
deep sky things in the sky than as a planetary scope.
For a planetary scope, you really want a long focal length so that you can
easily get magnifications of 200x or more with that EP.
Things will be somewhat fuzzy with any scope to some degree or another with
about 50x per inch of aperture being approximately the highest magnification
usable with any aperture.
FWIW, I have a telescope of 4.25" aperture and is 200" focal length. That
scope works wonderfully on the planets, producing excellent images that are
hard to compare to other scopes. At a recent telescope meet, I was seeing a
crescent with sharp tips on Mercury when all the other scopes could only see
that it was elongated. Then again, looking at any large deep sky object was
difficult to do as the scope really can't see that much of the sky. Getting
M81 and 82 in the same view was almost impossible to do.

--
Bob May
Losing weight is easy! If you ever want to lose weight, eat and drink less.
Works every time it is tried!

(Eddie) wrote in message . com...
So my question is if there is any way to tell whether image fuzziness
is a result of the scope or of the environment without looking through
a larger scope.

Yes - look at the same thing, with the same scope, every available
night for for months and months.

I know that's a trite answer, but it's the truth - and I learned it by
doing it.

The experts will give you loads of valuable and relevant advice
regarding collimation, seeing, cooling (of the scope), eyepieces,
learning to see, gettting experience, etc. etc. etc. Don't disregard
this, it's right - but it won't give you a satisfying answer. Just do
it!

Until you experience it yourself, you'll always be doubtful. Trust me
- after you've looked long enough, you'll be blown away by what your
scope can deliver - and 99% of the time it *IS* limited by seeing.

(To the experts; sorry if I've overstepped the bounds of giving advice
- you all know I'm a newbie, but this aspect is something I've
experienced over the last few months - not a distant memory as it is
for you. Evangelism of the converted and all that... :-)

Cheers
Beats