Should I bin 2X2 or higher when shooting?

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Johnathan Allison avatar
I am shooting with a ZWO-ASI585 MC PRO coupled with the Rokinon/Samyang 135mm F2 Lens. I am Undersampled right now with a res of 4.43"/pixel.  I am new and have gotten pretty comfortable with my setup and what to start exploring ways pull more detail out of my imaging. 

I am currently researching Binning/Drizzling and how I might utilize these either in the field or back on my PC. I was wondering what would  prove more beneficial. I don't get a lot of clear nights so I want to make the most out of my sessions and have anxiety of trying new things and possibly losing a whole night of imaging. A better understanding of what is happening would help with that anxiety. I will throw a screenshot of the astronomy.tools page below. 

If anyone has words of wisdom about this, it would be greatly appreciated.

Engaging
andrea tasselli avatar
What's you average FWHM?
andrea tasselli avatar
Incidentally, you'd want to drizzle not to bin 2x2 (which is the opposite).
Johnathan Allison avatar
andrea tasselli:
What's you average FWHM?

2.669 Is my median
andrea tasselli avatar
2.669 what? Pixels, I'd presume. If so you are already optimally sampled as you are.
Johnathan Allison avatar
andrea tasselli:
2.669 what? Pixels, I'd presume. If so you are already optimally sampled as you are.

I have no idea what I am looking at lol. also I picked a different set of sub from a different target. the 2.669 was from a different target. 

andrea tasselli avatar
At your image scale it can only be pixels. So it is around 2.5 pixels give or take 10% (maybe 20%). At the best of times, if you dither agressively, got good SNR on each single frame and got a very large number of them you can try drizzling 2x then apply deconvolution and then downsample to the original scale with pretty much no major effect on final SNR. Otherwise just leave as it is. Personally, I never found drizzling 2x to be of any benefit unless your median FWHM is less than two pixels, with the other caveats withstanding. Applying "smart" deconvolution (i.e., BXT) can lead to some serious issue unless all the concerening ceveats are complied with. Users be warned.
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