The sky early on Sunday morning (05.10.08) was the best I have seen in a long while. The Astroforecast Dot Org put sky transparency at about average but from where I was observing at 02:30 UT it looked a lot better than that. This wasn’t one of my usual sessions, instead it was a great chance to take my shiny new Sony a200 DSLR for a test drive, and believe me, I had no illusions that there were going to be dud shots a plenty and a lot of experimenting going on.
It’s one thing reading up on f/stops, focal length, ISOs and exposures . . . it’s another putting it all into practice. I thought I’d take small steps and start things off by trying my hand at photographing constellations. First on the agenda was Cygnus. Focusing on infinity proved to be a real pain in the neck and I probably should have had the foresight to set the focus ring on the 18mm - 70mm zoom lens earlier in the evening.
Captures were predictably awful, but I persevered. I was pleasantly surprised when I spotted Orion just rising over the roof tops to the south east at 02.44 UT. I quickly positioned the tripod and the camera and began shooting. I started off at f4.5 using ISO 800 and a 5 second exposure. I then upped this to 10 seconds and then finally 30 seconds. It was the 30 second exposure that won the day and offered up the best (albeit slightly out of focus) capture of the evening revealing both M42 (The Orion Nebula) and M43 (De Mairan’s Nebula) as well as the star Iota Orionis which forms the tip of Orion’s sword.
I returned to my original quarry of the evening - Cygnus, which was now sinking slowly towards the horizon. Using an f/stop of 3.5 and a focal length of 18mm I managed to capture this 30 second exposure at ISO 800. Not the most dramatic shot, but it’s early days. Like the Orion shot, light pollution was quite visible in this capture as was some chroma noise, but I managed to process the worst of it out in Photoshop. I should have had the foresight to take some dark frames (note to self: TAKE DARK FRAMES!).
The white giant Deneb can be clearly seen while the star fields and dust lanes of the Milky Way are just visible as they tumble down the length of Cygnus. The top of Lyra can be seen drifting slowly out of view while Vega1 hovers just above the roof tops. Over to the far right of the image can be seen the constellation Draco or as the ancient Egyptians called it Taweret which means one who is great after the goddess of the northern sky.
By about 03:20 UT the cold really was beginning to set in so I decided to put the DSLR aside, but before I called it a night I decide to do a little observing through the Bresser 10×50s. Turning the binoculars on to Orion, I took a look at M42 and what a view - just stunning. Randomly sweeping the sky, I eventually landed on Ursa Major and took a peek at The Horse and Rider i.e. the stars Mizar and Alcor. Turning towards the zenith I decided to take in another view of M31 before sweeping south on to The Pleiades and finally back to M42 in Orion.
All in all, I’m quite pleased with my first proper attempts at DSLR astrophotography but I’m sure I’ve got a long way to go yet before reaching the next level.
- Based upon excess emissions of infrared radiation coming from Vega, it was ascertained that there was a disk of dust around the star much like the Kupier Belt of our own solar system. Irregularities in this disk of dust also suggest that there is at least one planetary body with a mass equal to Jupiter in orbit around the star. ↩
Tags: Andromeda, Bresser 10x50, Cygnus, De Mairan's Nebula, Deneb, Draco, DSLR, Extrasolar Planet, Galaxies, Iota Orionis, Kupier Belt, Lyra, M31, M42, M43, M45, Mizar, Orion, Photoshop, The Orion Nebula, The Pleiades, Ursa Major, Vega