Category Archives: Photography

All Sky Camera Update

In 2020 I started a new job as a science technician in a school. A few months later the UK went into a coronavirus lockdown and I was told to do my job from home…which was an interesting challenge. We’d all seen it coming, so I’d already filled my home workshop with two carloads of broken equipment and antique science stuff in need of a polish, but it didn’t quite fill the time. So I started looking around for funding opportunities for…well, anything.

The Institute of Physics was offering grants for £800 for anything not-curriculum related and ideally relevant to the local area, and we’ve got a fairly dark sky, even from the roof of the school, and an all sky camera costs about £800…so I applied and they sent us some money. All Sky Optics, who supply this kind of thing, were hugely helpful both supplying the right bits and with lots of advice.

It’s been up there for three years now (it took a while to build as a project with students), without a break, in all weathers, taking hundreds of long exposure photographs each night, and then automatically stitching them together into videos each morning, all run by a Raspberry Pi and an astronomical camera.

As the name implies, it films (nearly) the whole sky with an ultra-wide angle lens, like an extreme fish-eye. The centre of the image is directly overhead, and the circumference of the circular image is the horizon. We’ve caught noctilucent couds, meteors, satellites including the international space station, the milky way slowly rotating, and quite a lot of seagulls. And the aurora. From our location it’s a reasonably regular thing, and wow, did it kick off last week. We normally get a green arc and some pillars on the northern horizon, but this one was directly overhead, with a lot of red in it.

A fractal-esque pattern of residue on filter paper, dark brown on off-white.

Fractal Filters

There’s some chemicals, even in a high school setting, that you can’t just pour down the sink. Some you have to neutralise, some you have to filter…some you have to neutralise to produce a precipitate, and then filter that.

These are in the latter camp. I noticed after leaving a particularly sludgy iron chloride suspension over a weekend that the precipitate in the filter paper had dried in a pretty fractal pattern, the larger surface area at the top of the filter paper and capillary action leading to a gradient of drying and cracking. I’ve been slightly more careful with further disposal methods, trying to find pretty examples.

Project Fish: Clachtoll Jellyfish Bloom

We took The Fish (need to find a better name?) over to Clachtoll on the west coast of the northern Highlands of Scotland to see what was under the surface. Good timing, it turns out, as a jellyfish bloom was going on. When conditions are right jellyfish reproduce in huge numbers all over Scotland, sometimes even resulting in issues for nuclear power stations!

Project Fish is the “engineering arm” of Fishing For Footage by Julia McGhee. (I use the term “engineering” loosely, especially in this context!)