[konstantinos75]

Hi

I would like to raise this interesting topic and hear the experts opinion about this.

After some research I have done, when someone is doing astrophotography with a CCD camera attached to the telescope, it is advisable to

* bin 2x2 the exposures with R,G,B filters; this will increase the SNR of the final RGB image; it saves you a lot of time, as exposure time is reduced to half comparing to binning 1x1. For example, if with bin 1x1 you need 5 minutes exposure, with bin 2x2 you need 2.5 minutes to get the same result.

* bin 2x2 is better be done from dark skies for taking many exposures in less time.
From light polluted skies is better go with bin 1x1.

* if you need to combine the R,G,B frames with the L frame, you must not use bin 2x2 for the R,G,B frames and bin 1x1 for L frame because in this way you will loose in resolution of the final LRGB image. Instead use bin 1x1 for all L,R,G,B frames.

* for narrowband filters you must bin 2x2 for Ha, SII, OIII to get the best result in less exposure time. But in case you need to combine these filters with L you must go with the bin 1x1 rule for all filters.

* if the image scale of your imaging device is less than 0.5 arcsec/pixel (for example you have a long focal length telescope) is better bin 2x2 all the L,R,G,B,narrowband frames.

I would like to see if these assumptions can be justified and if someone has some arguments about this.

Thank you
Konstantinos