Quote:
Originally Posted by JohnH
I must have expressed it badly for a given temp/ccd/gain/exposure noise will be fixed whereas signal will vary with the brightness of the object, thus for a short exposure faint details are lost as they cannot be distinguished from the noise. We use longer exposures or multiple exposures to deal with this.
I take your point re s'ware binning but it has been my experience that s/n is better with hardware binning - I guess it depends on the chip.
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This has been a very interesting thread.
The 8300 seems to not be the best chip to demonstrate the advantages of hardware binning, and good at showing when its NOT usefull!.
So, yes, it does seem to depend on the sensor and I agree its all about read noise (when the sensor allows a binning advantage).
My 6303 (NABG) sensor has high read out noise but large well depth. 100000 per pixel cell and 330000 for register cells.
Anecdotally anyway, I get better S/N with hardware bin 2*2 because the 6303 has high read noise and its difficult to overcome read noise in dark skies. It requires very long exposures.
Binning with urban imaging, even with short exposures with an 8300 sensor does appear to be fruitless.