Hi Evan
There is no doubt that the Astro cam image is clearer. I concur that the fact that it's a mono cam would help with that considerably. It's a good comparison to see. Often, as we all have different equipment, it's hard to tell what is causing what difference. Good on you for posting it.
As far as F ratio goes, lower f, lower required exposure time for the same data. That being said, I have an f10 SCT which is " slow " by AP standards and I live under skies that literally look like daylight when it's cloudy. The trick there is to trade in a good f ratio for some good old fashioned perseverance.
