[doppler (Rick)]

Larger aperture scopes are more about higher resolution, extra light gathering is a bonus. I can defiantly notice the difference between my smaller scopes and larger ones.

Here is a 5 sec single sub at iso 6400 with a 10" f5 newt and canon 1100d. And now added, a 10sec iso 6400 with a 120mm f5 achro and canon 1100d, this is from the archives so not the best comparison to use.