Alright people tell me the difference between an S

Alright people, I want to know your opinion. I've had an SCT (10") since 1993 and live in a light polluted area (mag. 5 on a really good night). I just bought a 4" APO refractor. I want to know what I can expect in performance. (I know light gathering won't be what I'm used to). I've also owned a 5" SCT which I sold to buy the APO and I owned a 80mm Achromatic scope, which i have also sold. You APO nuts out there, please tell me I did the right thing. I still have the 10" and am thinking about building an observatory for it and the 4" APO. What do you think? Any opinions would be greatly appreciated. Thanks,

Sounds like you have two great scopes. Take the time to use the 4" and learn what it can do. One advantage you have with it is that it is more portable than the 10" so, as I'm sure you're finding out, you're using it more than the SCT.

As far as building an observatory - go for it if you have a site to accommodate it. Isn't that part of the hobby? Playing with equipment and enjoying the night sky.

Jason,
FWIW,I think you made an excellent choice. I have a Mewlon 210 and TMB 100/800 which I have had mounted side by side on a Giro GR-2dx mount. The TMB is a real nice "finderscope" for the 8" and is much preferred for lunar/planetary standing alone for the quick cool down and ease of set up.

Regarding an observatory, I probably would use the money, sell the 4" and upgrade to a 5" APO. however, YMMV.

Good Luck, Owen