Ok, so I want a large scope to have greater resolution power; so what is the telescope for me?
Ok, this question is right but not too much, for 2 important reasons: 1) the seeing; greater is the scope diameter, worse is the seeing; a 25 cm scope can be used at maximum resolution power only few days per year; a 40 cm scope can be used at maximum resolution power almost never! So you’ve gotta make a choise: observe 10-20 days per year at very high resolution, so you can buy a telescope of 30-35cm; or observe 100-200 days per year at mid resolution and buy a 15-20 cm scope. The other problem is the mount: don’t undervalutate the mount of the telescope; a good mount costs more that the optical tube, so if you wanna buy a 5000$ scope, you’ll need at least a 5000$ mount!It is completely useless to have a big and good scope if the mount is little and with no precision, even if you observe the planets. At last I can answer to your question: if you wanna buy a good and big scope you can consider a SCT of 20 or more cm on good equatorial mount (which can costs from 700 to 1500$).
