Caelus,

The jump from a 6" f/8 to an 8" f/6 Newtonian is perhaps the most cost effective one in amateur astronomy. The 8" OTA will be the same length and the weight won't be all that much more. I would strongly consider getting the 8" if I were you.

You shouldn't let your expectations about telescope performance get too inflated. Even through a very large telescope Uranus and Neptune are not very impressive.

Dave Mitsky

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