The air is a bit more moist tonight, so I slipped on the dew shield early.
For most of the night the seeing seemed good but not great, at times it looked like my collimation was off a tad. I decided to give it a nudge, removed the dew shield to get to the secondary screws, and lo and behold – both seeing and collimation sorted themselves out! I'm not sure what weird sort of currents this dew shield (no heater!) is causing, but now everything is clear as a bell, at least intermittently.
I'm glad I found my dew shield's dirty little secret, as I was rewarded just then with a gorgeous view of Antares B, at 360x. I've never split Antares from my backyard before, so I'm kind of chuffed
Cheers
Steffen.