An all-sky camera (or nearly all-sky)

The other day I mentioned that I'd swapped out my guide camera. It turns out it wasn't necessary, and so now I've got an old ASI120MM in reasonable condition.

I decided to try setting it up as an all-sky camera. The camera comes with a fish-eye lens, and all you have to do is connect the computer via USB and use some time-lapse software to make a video. I put the camera on a bit of angle iron and attached it to a mini-tripod (see the photo). I was entertaining vague thoughts of putting it onto my mount for an extra view, but I don't think I can run three cameras simultaneously using ASCOM.

For image capture I normally use SharpCap 2.9. It's a free download, although more recent versions have become paid software.

As always, setting this sort of thing up takes a few goes. There are options that have to be tested out and tweaked, calibrations like dark frame subtraction to be worked out, exposure times to be lengthened or shorted, output formats that work better or worse, and of course, you often just try the wrong thing.

Also, inevitably, clouds roll in.

So it took me a few days, but I got this video. My study window faces north, and so you can see the summer equator constellations wander past. This is best seen in full-screen.

At the start, you can see the Pleiades, followed by the Hyades asterism (Taurus), followed by Orion and bright Sirius. Procyon follows, as always. Below that, Gemini - Castor and Pollux move just over my neighbour's roof. Between clouds, you can see Leo and Corvus come past, and Spica and Arcturus are just coming into view as the Sun brightens the sky (and more clouds obscure it).

I've also added a few stills taken from test runs. You can see an aeroplane (with the strobe lights clicking along next to the trail) and what I think is a meteor (the trail is dim at the ends and bright in the middle).

For the technically-minded, the stills were taken before I had created a dark-frame for subtraction. This calibration identifies and removes the white speckles over the frame.