Quote:
Originally Posted by Merlin66
I'd love to help if you can explain how you currently measure the SNR in your images....what "improvements" are you looking for????
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I'm looking for the starting point. As in, I make a decision to go for target X from location L using gear G (camera with specific settings, mount capable of handling M minute exposures consistently).
I need to answer questions like this:
* I can do this image over multiple nights, what's the best T value I can use to get the maximum theoretical SNR in the result?
* The weather is looking like rubbish and this night is likely it, or I'm at a dark site for just a night. Given I liked 20+ images per channel to process I want to take (and therefore constrain T), what camera settings do I use to get maximum theoretical SNR? This can also help determine if target X is actually feasible or I should pick something different.
In both cases, T has a max value of either M or the Sky Limited time at L (SL), whichever is smaller (actually I suppose there's also a limit based on the camera's capacity). Although I assume if SL < M, going to T = M won't hurt, but is just a waste of the extra time? This is one of the questions I'd like to know, because if I work out that for a number of common situations, that I should use a value of say 30 - 75 seconds, I'll just pick 60 sec to cover those cases, etc. If it's 200 to 280, I'll pick 300 sec just for the simplicity.
Is this all obvious to everyone else and I'm missing something basic here?