experiment bob (1 Viewer)

I bought one of these recently 2nd hand.

http://www.celestron.com/c3/product.php?ProdID=203

comes with a 45deg prism. ANy suggestions about these affecting image quality for terrestial viewing? How do I work out what is a good prism and what will deterioate the image?
[do i mean diagonal? is that the same as a prism?]

I have some ep left over from my pentax 80mm. inc a 16mm uwa williams optics. (75x 82 deg)

Not expecting it to be much use past 80x due to dull image but in theory it would go over 100x.
I think in english ave light it will be impractical to push it past 70x.[focal length=1200]

Have used cheapy mak scopes and been impressed with the lack of colour aberation, however this is balanced by a lower contrast image.

Scope should arrive next week...just in timef for my birthday....:-O

The 45 degree prisms are junk, there's no other word to use. They're cheap Schmidt roof prisms without phase coating, guaranteed to ruin the image of any telescope. Fortunately there's a flip mirror inside the scope that can erect the image, but it reverses right and left. It probably uses standard aluminum coating, so any 90 degree star diagonal prism will be brighter, but that would still reverse right and left and cost about $30-$40. I'd start with the internal flip mirror which ought to be OK.