Thanks Mark, I hadn’t considered nearby stars to the target star so that is a very useful tip for me.
I’m having a little trouble with establishing what the SNR is on any given star. Tring to do it in Pixinsight, and to be honest as there is so much conflicting information online I’ve no real idea what I’m doing!
I took a calibrated 2 min sub, debayered and extracted the green channel (OSC camera).
The I created a preview box right around a star, and another on a patch of background sky.
Then I used the e statistics function to look at the mean ADU value of the star (3420) then divided that by the stddev of the background (57) to get 60. So is that a SNR of 60? Pretty flow for a star close to saturation!
I have attached a pic of the preview boxes I used, coupled with a .Fit file of the green channel I was inspecting.
Any help greatly appreciated!
Edit: seems like the .fit is too large
