[Terry B]

Originally Posted by renormalised

You notice how most of the professional imagers (i.e. astronomers) take pics with instruments with FL's as low as f/2. All the shots from the prime focus cages are about that long in FL. Shots at short FL's are probably harder as you need excellent focus (and look at how hard that can be to get)....long FL's are either for peeps who like imaging planets and such, or for people with the patience of Job, who like to sit around for hours trying to get enough photons just to see anything!!!

Don't me wrong...I like both. They both require practice and have their good and bad points

I like the longer focal length imaging but then I like to see images of galaxies and PNs (and most are pretty small). Not much point taking widefield images when the subject only fits on 10 pixels.
You can always take the same image throught the slower scope and bin it for exactly the same brightness as taking it through the shorter focal length scope.