I’ve been going bush and camping in the High Country, for over 40 years and nothing impresses me more than a clear night sky that’s not affected by light pollution from urban areas. In 2009, it was reported that one-fifth of the world’s population can no longer see the Milky Way due to light pollution, which is incredibly sad if true. Fortunately, we are a little luckier and my ultimate experience happened once in the far outback where, under a full moon and blazing stars, it was possible to read a book without any supplementary lighting. Mind you, my eyesight was a lot better in those days. That said, for some reason, I’ve never given any consideration to taking photographs of the night sky until recently. My first attempts earlier this year, while camping on the Nunniong Plains was far from impressive, but it gave me the impetus to keep going, as well as practice post-processing of night sky images.
Ideally, night sky photography is best done with cameras that have a larger sensor format than the one that I own, simply because they have somewhat better image-noise characteristics and you can get wide angle lenses that are generally faster (larger aperture); the Nunniong Plains shot was taken with a 14mm f4 (35mm equivalent lens). Wide angle lenses are favoured for photographing the Milky Way Galaxy, but it doesn’t mean that you can’t get interesting shots with just about any camera/lens combination, especially when you consider what astrophotographers of yesteryear had at hand. So, with due preparation and effort, it’s possible to achieve some pretty impressive results with almost anything. However, as with any photography, what you take really needs to tell a story rather than just seeking technical perfection, unless you’re an astronomer or the like, where the detail is all important. Afterall, the starry night has been visualised in many different ways over the centuries.
Depending on how serious you want to be about astrophotography, you can go with minimal gear, or open your wallet and go the whole hog. The minimal gear basically involves a camera and a tripod, the whole hog involves tracking mounts, expensive cameras and tripods, and even telescopes if you want to start some serious deep sky photography. But for me, longer lenses aren’t that ideal for the sort of photography that I like, as they place you into deep sky territory, where every technical issue that can cause problems is magnified manyfold. Either way, faster lenses and longer exposures mean that more light is captured by the camera for better results, but you can’t take exposures that are too long, else you begin to see star trails (unless that’s what you want).
The latter is the reason why dedicated astrophotographers use tracking mounts, which are even available for small cameras, as they ensure that the camera’s lens remains pointed at the same spot while the earth rotates. While I do have a tracking mount (a fairly old design, not the friendliest to use and very heavy to lug around), I’m now more interested in astrophotography using commonly available gear, doing what anyone can achieve with less complex equipment. Whatever you use, a sturdy tripod is still essential and while mine isn’t the heaviest, a Manfrotto 055CLB alloy tripod with Benro GH1p gimbal head, it’s reasonably sturdy for what I like to achieve.
Specialised software is also useful and much of this is available free from many sites (I won’t go into this too much, as the options could just about cover a story on their own), but one very useful tool, for Windows users, is Stellarium. This program will show you every star, planet etc in the night sky in your region, so if you want to photograph something specific, it’s really easy to find it using Stellarium. These sorts of programs (or apps) are also available for smart phones, but it’s much easier to see things on a larger screen. With Stellarium, you can see pretty much every recorded star, nebula etc on the screen (zooming brings in more detail) and if you click on anything, it comes up with a full description. And it does a lot more, making it fun to use even if not taking photographs.
As with most photography, the determining factor is always going to be the weather and you can just about guarantee that you’ll only get clear skies on those days when you can’t get out with your camera. The ever present frustration for astrophotographers everywhere is that you are completely at the mercy of the elements and, in summer, you can be sitting out in the middle of nowhere well into the late hours waiting for the sun to go down (which is why this post, started last year, has taken so long to finish). That’s why winter is often the better time of year for astrophotography; darkness comes quicker (in a relative sense), the skies are clear (more often than not), and there is less haze (heat and otherwise) to cause issues. Also, the cold air helps to keep the sensor cool, allowing better results.
Once you’ve selected the ideal location (weather permitting), you need to set your camera to fully manual control, so that you can adjust focus (usually set to infinity), exposure (between 10-20 sec depending on camera and lens) and ISO (as low as possible to suit the exposure time) to what you require. Getting the technical side sorted out can often be a matter of trial and error, but with digital cameras it’s easy to review your shots and try again. Sometimes the blaze of glory overshadows what you wanted to photograph and the composition fails big time, especially when you forget dark-frame subtraction (a second exposure in-camera that reduces sensor noise), but you just rinse and repeat.
However, as I alluded to at the beginning, when taking stellar photographs, I prefer to include something interesting of a terrestrial nature, rather than just taking starscapes. I’m not so much into astronomy, but showing the relationship between man, earth and the universe. That’s why I like to take photographs like those which I posted from our recent trip to the High Country, using wider angle lenses over telephoto lenses. It’s also another reason why this post has taken so long to complete, as finding ideal locations where those three elements come together hasn’t been easy. Some things always take much longer to achieve, but you just keep an eye out all the time and sometimes the chips fall your way.
When it comes to astrophotography, I’m a complete novice, but it’s just another thing that I like to explore and see if I can produce something interesting once in a while. I feel for those dedicated astrophotographers that spend long, cold, hours during Winter’s nights producing outstanding photographs that only come from such dedication. But if you want really good advice from some of the most experienced people in the business, go to IceInSpace.