The Triangulum Galaxy

The weather recently has been fairly sunny and warm, which is great but, means the skies are cloudy – hazy at best at night.

Finally over the past few days, the temperatre has become more like mid-October and there’s been some clear skies!

I decided to seek out a new target, M33 The Triangulum Galaxy. It’s not far from M31 The Andomeda Galaxy and at the time that I shot, was located directly above Jupiter.

The Triangulum is our closest galactic neighbour after Andromeda at 2.73million ly away.

I had the easiest setup yet – I levelled the tripod with the mount facing North, set it to start from ‘Park’ position, slewed to Jupiter, then slightly adjusted the camera, not the mount, to centre the planet in the frame. I used Jupiter to focus and snapped a quick single shot of the planet with moons. I used my Bahtonov mask to focus, which seemed to work well.

I dialled in M33 and once it had slewed, took a test shot of 5 secs with ISO at 3200 – I was delighted that the galaxy clearly showed right in the centre as a faint blur, so started shooting at 25 seconds, ISO800 f/5. A bit later in the shoot I adjusted to f/4 and ISO1600. Amazingly, my AZ mount seemed to track better than usual and the galaxy stayed centre-frame throughout! Of course there was some rotation due to using an AZ mount, but this was easily cropped out in processing.

I also experimented with using existing calibration frames – a set of Flats, Dark Flats and Bias from my last Andromeda Shoot, and some Darks (I’ve not really used Darks for ages) that I recently shot outside on a cloudy night. These seemed to do the job perfectly well, so I’ll definitely use this approach again.

For a bit under three hours total integration, this is a decent result. Next aim is to get another three hours and combine the two sessions to achiever more detail.