Finally, after a month I had half a night with clear sky on Sunday morning, although a bit hazy. I was also a bit too eager to get the scopes up on the rig so I noticed afterwards that balancing was not perfect. Balancing is also a bit tricky with a dual rig. So my EQ8 had to fight a bit and I had to throw out a bunch of subs due to jumps in the guiding. So I ended up with 48 x 3 min RGB from the ASI071 (gain 200, offset 30, -15°C) sitting on Esprit 150, and 67 x 3 min Ha (Baader 7nm) from the ASI1600 (gain 139, offset 59, -20°C) sitting on Esprit 100, so totally nearly 6 hours from when the sky cleared between 02.30 to 06.00. Stacking and calibration (only master dark subtraction) in PI, processing in PS.
Sh2-140 is apparently largely hidden by the dark nebula called Lynds 2304. If you want to see a nice close up (caught with an 8" SCT) of the central part of the nebula, with some clear pillar structures, and an interesting write-up about it, have a look at Jason Guenzel recent post. He calls it the Hidden Nebula:
https://www.astrobin.com/377160/
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