Tl/dr version: Pics used to be good, now they suck. Dust moves. I’m lazy. How do you do it?
Some of this is specific to Astro Pixel Processor, other parts are generic questions. My setup consists of a Losmandy G11, Zenithstar 73, Focus cube, QHY533c, on mount Mele q3 mini computer. It’s all essentially permanent and I operate it remotely from indoors using Nina.
What I used to do used to work for multi night imaging, I’m talking within the last few months. I would pic a target, shoot a bunch of light frames for a couple or a few nights, collecting on average 12 ish hours of data we’ll say. During, before of after one of those nights I will shoot Darks and Bias frames. Likewise, one of those nights, maybe the same night, maybe not, I will shoot Flat frames. These are done with a tracing tablet and the Flat wizard in Nina. Usually goes very smoothly and quickly. Now I have a bunch of light frames and all my calibration frames. I’d load those into APP, I would uncheck multi night box, and I’m off to the races, at least on to post processing. Picture would be as expected and I’d save it for photoshop later.
The last couple of sessions of the same work flow I get horrible “dust mote” looking circles in the completed stack out of APP. Like I didn’t use any flats. Keep in mind I’m in Tucson so dew isn’t a thing. Well, wasn’t. Lately however, it’s been quite cold and wet. Am I seeing dew/frost, dust in a new spot because of dew etc? What it is isn’t that important I don’t think, what is important is the fact that the flats I took maybe two nights ago are not correcting for the “stuff” and it’s new position tonight. Does that make sense? Also I’ll point out during one of these multi night sessions nothing in the image train is moved except for focus changes.
To rule out anything really odd, the other night I shot my Lights, and all calibrations in one evening. Into APP and out comes a good picture. So I’m thinking my thoughts above are correct.
So what is your work flow for multi night sessions? Do you take flat frames every night? If so, when do you do them, before, during, after the session? My flats are not automated so I don’t want to go out in the middle of the night to do them, yeah I’m lazy.
Also for you peeps using Astro Pixel Processor, how do you load the multi night subs into the software? It’s not super easy finding a lot of instructions for APP.
Sorry this is long winded, but I certainly appreciate all the help I receive from all of you.