CandT wrote:
As a beginner with a relatively cheap 500mmx114mm (f4.3) newtonian, what am I
likely to be able to see well?

Thousands of things. All the Messiers (although some, e.g. M101) will
require excellent conditions, hundreds of NGCs, the planets out to
Neptune, loads of asteroids, double stars ....

Try _Turn left at Orion_ for good starter-lists.


The optics seem pretty good, though with the 2 eyepieces I have (17 and 10mm
plossl's), the top magnification I can get it 50x :-(

x50 is fine for hundreds of DSOs, and too much for some. You may begin
to wish you had a 32mm Plossl!

Am I going to need filters to see nebulae?

UHC, and especially O-III help on some emission nebulae (esp.
planetaries for O-III), but don't rush into it. There's literally
hundreds of things to enjoy before you spend 80+ quid on a decent
filter.


What magnification is best to get
good views of jupiter

Magnification equal to your aperture in millimetres.

and pluto?

Forget it -- too feint for your aperture.

Also see:
http://www.astspace.demon.co.uk/nigh...lyNightSky.htm and
http://www.nightsky.org.uk/

--
Best,
Stephen
http://www.astunit.com