Lately I’ve become interested in astrophotography. Not so much shooting galaxies in deep space (yet), but capturing star trails and the Milky Way are my two of my latest challenges (along with panoramas, HDR, and all of Photoshop. Focus, haha, is not my strongest point).
So far the most important lesson has been that you can focus past infinity! Who knew! Turns out beyond infinity is quite fuzzy and doesn’t make for the greatest photograph. I had my best luck by having the camera focus on something at least 10 metres away, like torchlight lighting up a tree, but I learnt the hard way to check, check, then check again zoomed in as much as your camera will allow on your LCD. Infinity is often slightly to the left if where it’s marked on your lens; on my to-do list is to mark exactly where it is on my lenses.
Otherwise, many of the usual things for long exposures apply to astrophotography:
- Remote release or timed release – no vibration from shutter pressing
- Turn off IS/VR
- One I keep forgetting: Take a black exposure, ie with the lens cap on. It can be used to remove noise by stacking software
- A focus trick: Turn off auto focus. Look at Live View, zoom aaaaaall the way in with zoom buttons, manually focus on a bright star until it’s a sharp point. Don’t touch the lens again!
For the Milky Way:
- High ISO
- Likely no longer than 30 seconds exposure, otherwise you’ll start to get star trails. Test this however, it is dependent on your focal length
- Get that black exposure!
Conversely, for star trails:
- Low ISO
- 20-30 second exposures, but play with this. The longer the exposure, the more noise, but also more stars
- Multiple exposures, for at least an hour
I strongly recommend Charles Niauton’s “How to Photograph Stars” tutorial, it helped me immensely.
For star trails, I’ve had some reasonable success with Star Stax. It’s not perfect, but it was how I was able to put together this star trail taken over my house, in suburban Brisbane (yes the house is ugly, we’re planning a renovation which has its own blog at Gecko Reno).
I’d like to say I knew the Southern Celestial Pole was there, but I did not. I was expecting some arcs and mostly just out there to learn and practise, so it was quite a kick to see the pole. Given it’s my first attempt I’m not unhappy with this at all.
My first Milky Way is less successful. This was taken up near Ballandean, in Queensland’s Granite Belt region. The Granite Belt is up to 900 metres above sea level, and the coolest region in Queensland, so it makes for beautiful clear skies (I wrote about a previous visit to the region here). Unfortunately the weather wasn’t really playing ball; a strong wind blew regular clouds and rain squalls over us so I only had a short window to play in. This is the best attempt, but I’m not really happy with the noise or the composition or the wow factor of the stars.
The following night I had another short go. My husband insisted on trying some 60 second exposures – I was dubious thinking we’d end up with star trails, but actually that was ok. Less ok is the noise and the hot pixels, but then they’re only visible when pixel peeping which is a bad habit of mine developed from submitting images to stock photography sites. I’d be interested to know which photo people prefer!
Will also liked the stars being blue. Post-processing these images is an art in itself which I can’t claim to have come to grips with but I’m working on. These Lightroom presets by David Kingham, and the accompanying videos, have helped immensely however. The presets are donation-ware and I’ve donated, if you find them useful I recommend that you do too. I can vouch that sussing this stuff out on your own isn’t straight-forward, especially the white balance.
On a final note: my uncle sent me this interesting video of a lecture given by Barbara Cunow. Cunow is an amateur photographer who’s photographed all 110 Messier objects, with minimal equipment and terrible light pollution but some smart photography and processing techniques to compensate. A lot to learn!