Hi all,
This all came about because I'm using an ASI 1600 on my Esprit 120mm which is fine, but if I stick it on my RC10, I'm oversampled. My understanding is that for a CMOS, you might as well bin in post, not when capturing, as the advantages of CCD's doing a single read of four pixels doesn't apply here. However there are lesser SNR advantages to be had from binning in post. I've also read that Binning at 2x makes your sensor 4 times more sensitive.
Okey Doke.
So if my unbinned luminance exposure is 1 min and I'm planning to bin x2 in post, do I expose the same as I normally would (1 min)? Or do I expose for 15 secs, knowing the binning will bring back the detail that has been lost?
And then in post, you have the choice of true additive binning, or averaging, which has the advantages of SNR without allowing out of range values.
So there are a few questions I'm wrestling with;
- Am I correct in thinking that binning 2x makes the sensor 4X more sensitive? So the information gained in 1 minute would then be gained in 15 seconds instead?
- Then you add the filters which in my case increases exposure times by multipliers of G2.7, R3, and B3.7 respectively, turning those 15 second exposures into exposures of G41, R45 and B56 seconds.
- Now I don't seriously want to compensate for the filter transmission and QE by shooting darks for three different exposure levels on the colour filters. Is it possible to shoot more subs to make up the difference? How many more subs would be required to get the same SNR on all channels?
Any help appreciated
Markus