I know I keep posting totally amateur questions, but I'm still just a bit confused about focal length and focal ratio. I want to see if I have this correct (before I buy a second scope). I'm this close to pulling the trigger on an 8" SC.
I currently have a 6" SN with a focal length of 762mm and a focal ratio of f/5. If I understand correctly, this would be better than the 8" SC for a lot of DSO photography because of the fast f-ratio and the wider field of view due to the short focal length.
The 8" SC, which has a FL of 2032mm and f-ratio of f/10 would be better than the 6" SN for planetary photography because of the longer focal length - thereby bringing the planet closer, even though it's an f/10 scope, the brightness of the larger planets isn't as critical with the slower f-ratio.
Is this correct?
If my understanding is right, I'd need to start applying a focal reducer to image some of the larger DSOs with the 8" SC. Though it might do a better job on the smaller ones that would fit in the 8" SCs FOV.
I guess what I'm trying to figure out in my mind is whether or not it's worth it for me to make the purchase of an 8" SC to image Jupiter, Saturn, Mars, Venus, and smaller DSOs.