davee1 - 7/26/2009 1:27 AM
Dont know much about telescopes, but I sure like that Celestron FirstScope.
Will that one show an upside down image?Â
I dont want one that shows an upside down image. Would like to use it as a spotting scope too...so upside down aint right.
A Newtonian telescope (which the $49 Celestron FirstScope is an example of - these user mirrors rather than lenses) will have a reversed image (up is down, left is right) if you look through it as you would normally situate yourself. i.e., the telescope facing forward at your target and you sitting behind the telescope. If you reverse yourself, the image will be normal (up is up, left is left). By "reverse yourself", I mean: Aim the telescope at the target, then you stand in FRONT if it (looking backwards so to speak). The telescope will be pointing back behind you. Obviously you can't stand RIGHT in front of it, you have to be off to the side a little, so the telescope can peek just to the side of your body.
You can get a "correct image" prism for a telescope, but these do not often work well with a Newtonian scope (like the FirstScope). They are more for refractor telescopes. Note: The $15 refractor scope mentioned in the first post in this thread would probably not work with a prism correct-image diagonal either. First, such a diagonal would cost you several times more than the $15 scope. Second, that $15 scope has a focuser that depends on friction. It would not be heavy duty enough to support a prism diagonal. Third, that friction focuser probably does not have enough travel to adequately focus a prism diagonal.
That Celestron looks like a dandy little telescope. For the price (which includes a tabletop stand!), this scope looks well worthwhile. I think I'll buy one for "quick looks" - no setup required - for when I don't want to bring out a bigger telescope. You won't be viewing great planetary detail with such a small scope, but they're not designed for that. These small ones are "wide field telescopes" that are meant for "taking in the big picture" with a large viewing area. This one looks like it would really excel at that, especially with the supplied 20mm eyepiece (15x). I think the supplied 4mm eyepeice (75x) is too much magnification for this little scope to handle well. A 6mm (50x) would have been better maximum magnification choice IMHO. 15x-50x is what I use for my widefield viewing.
