Thread: 10 or 5?
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Old 26-07-2018, 11:54 AM
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LewisM is offline
Join Date: Aug 2012
Location: Somewhere in the cosmos...
Posts: 9,450
Originally Posted by luka View Post
Amongst other factors the optimum exposure time will depend on the amount of light pollution. Your optimum (sky-limited) exposure will not be the same as for someone else. My camera has a similar read noise like yours and 3min is the optimum sky limited exposure for my location (<5km from Perth CBD).

If you expose for longer than sky-limited you will not improve the SNR but you will lose dynamic range. You should not be guessing, the optimum exposure is relatively easy to calculate, see this great IIS thread by Ray.

There is also a PI script called CalculateSkyLimitedExposure (or something similar).
Thanks - it is exactly the loss of dynamic range I have been concerned about, and hence why I am reading up around it.

Doing the PI script, I get an Antsey Limit of 22seconds...yeah Gonna do 4.5x10e77 exposures....(didn't matter if I used a starless of normal image - got the same result time and time again)

Thanks everyone - keep the topic alive

Last edited by LewisM; 26-07-2018 at 12:17 PM.
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