I don't wish to start any argument's about resolution or brightness , what I'm about is the largest aperture that performs best considering the average atmospheric conditions most amateur astronomy's face seeing fine detail .
Imagine looking through a nice 30" dob at Mars at say 300 Mag then moving over to a top 8" refractor at the same mag that showed a finer image but less bright .
From memory I remember it was stated that a 9.5" perfect scope will show contrast on things like planets as well or better then larger scopes at the same location .
Your thoughts please .
Bobby.