Grayscale conversion for photometry from raw images

[ChrisCiel]

Hello Han,

I was wondering if there was any practical way to get some grayscale images from canon raw images, after calibration and plate solving, so as to perform photometry on all pixels at the same time, so as to get a better SNR, something like CV or clear filter, but not TG TB TR.
The goal is to for deeper in magnitude than in TG.

Thanx in advance for any reply.
Christophe

[han.k]

If you bin 2x2 the images you will get a gray scale so CV=clear view. The R, G,G, B pixels will be combined in one pixel. That would help maybe a factor sqrt(2) so improve the SNR with a factor 1.41. The bin 2x2 is available in the popup menu of the photometry tab.

Then you could also group stack the images in groups of 2 or 4, either in TG or CV (2x2). This ids available in the popup menu of the photometry tab.

I hope that this work for you.
Cheers, Han

[ChrisCiel]

Thank you Han.
I will try the first method and see if this improve the SNR.
I know about the possibility of stacking images, but this second method will inevitably degrade the temporal sample, which I prefer do not.

Clear skies,
Christophe