Nice one Greg, glad you're liking it
Everytime I've tried raising the logic of high QE and low read noise, I've been virtually slapped down like the heretic I probably am
The 183 has very low dark current, so typically the shot noise is higher than the dark noise.
So far, I've resisted the temptation to go below gain 50, as below that quantisation noise becomes an issue...but short subs are the order of the day with my f/4 newt.