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Is this bad seeing??
The last couple of nights have been frustrating.
Friday night I decided to image M74 and its supernova, the problem being it doesn't clear my roof until 11.30pm, and then at 20 deg alt. So a particularly low surface brightness galaxy, low in the murky light pollution, and the results aren't pretty! Guiding was all over the place too - I suspect a combination of poor seeing/low altitude and backlash in the Dec axis.... I had some pretty crazy graphs.
The first graph is guiding in the wee hours of Sat am.... I'm sure I was chasing the seeing, it did improve by adjusting up the min move to 0.5 (no image of this)....
The second graph is from about 20 hours later.... no guide output though, higher up on Dec 0. It shows I need some polar alignment adjustment with the overall dec drift, but the oscillations can only really be seeing - am I correct??
These graphs are a scale of 2.1 arcsec/pixel.
Last night I could only manage FWHM values of 4-4.5, when earlier in the week at the same location, 2.5-3.... hair pulling stuff!
The last two nights have been very warm compared to recent, and very dry.... from what I've read dewey nights are often better seeing? Maybe I should have stayed inside!
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