Please forgive me if this sounds a bit know it all like. But I'd thought i'd mention this as I see it happen alot with new users. Your telescope may need to use its diagonal to get the correct focal lenth for your eyepieces, otherwise you may find yourself winding the focaser all the way out and still not getting those stars as pin points instead of cotton balls.

Yeah OK i'll admit it....I did this with my first refractor, but that was years ago OK.