You sure get nice results with your overloaded mount


I use my mount nowhere near capacity- if I polar align carefully, I can do a 15 minute unguided exposure with an 800mm lens and the stars will look round when viewed 1-1.


Quote Originally Posted by tkerr
This thread can explain it better than I can here.

I'm not sure what the guy in that thread means by "doing the math". There is no math. The only differences between the sum of 10 60-second exposures and a single 10 minute exposure are read noise and clipped highlights. As long as you take a long enough exposure so that read noise is small and a short enough exposure that you don't clip highlights, there is no real advantage either way.


Quote Originally Posted by tkerr
An assumption that many people make is that if you stack 40 x 30 second exposures that it will equal a 20 minute exposure.

I'm one of those people, apparently. I believe that the only differences are the two I mentioned above. Then again maybe read noise would be a factor in a bunch of 30 second exposures.


I think there is a lot of confusion about this- I've heard people say you need a single long exposure to get dim details, or who knows what else. On the other hand, maybe I am the one who is confused