Aiming for the stars: An introduction to Astrophotography

Abhilash PavuluriSep 10, 2017 15:20:45 IST

Every time I see a picture of the stars or constellations, or even photos of a Deep Sky Object(DSO), I can’t help but wonder at our place in the universe. Carl Sagan’s words couldn’t have been more right: we are but a pale blue dot in comparison.

Film photography. Image: Pexels

Thanks to the milestones in digital imaging, we’ve been able to observe and record as much of the universe as we can: right from humble photos of the moon to complex observatory setups to capture DSOs, amateur astrophotography is fast becoming both an enjoyable hobby and an important research tool for many scientists. Indeed, even without equipment, one has the chance to find galaxies based on image data at websites like Galaxy Zoo and the like.

So what *is* astrophotography? Simply put, it’s taking pictures of the night sky. But that’s just the gist of it. Even in such a niche category, the photography possibilities are endless, based on one’s patience, and more importantly, budget. In this article, we talk about the most popular methods of astrophotography along with something that fits a more suitable budget for beginners.

Photographers take pictures of stars and the Milky Way at Rdum il-Qammieh, outside the village of Mellieha, Malta. Image Credit: Reuters

This article assumes a few caveats: that you have a basic understanding of astronomy and photography. If not, Sky and Telescope is a great website to get yourself acquainted for the former, while our own photography column provides some insights into the latter.

The article also assumes that all types of astrophotography are done in a dark sky where

Types of Astrophotography:

Like I mentioned before, it all comes down to the amount of time and money you can into this field. But there are broadly 3 or 4 popular categories of amateur astrophotography:

• Widefield Astrophotography(with Digital cameras):
  Perhaps the easiest to get into if you have no idea about imaging, wide field astrophotography simply involves using your digital camera setup to take photos of the night sky. No more special equipment(although you can get fancy if you want to). While a DSLR is most suitable for astrophotography, any camera with M mode and a decently wide lens will do. So, what kind of objects can you photograph with a DSLR camera?
  1. The Milky Way: perhaps the most sought after wide-field object to photograph.
  2. Constellations: in case the Milky Way is not up yet, photographing constellations is an enjoyable and educative alternative.
  3. The Moon: quite a niche area but a popular one, especially when studying craters.
  4. Very bright DSOs: like the Andromeda Galaxy or the Pleiades Cluster.Wide field astrophotography is the least equipment intensive field there is(to begin with). All you need are a camera and tripod(the latter is really important).  While we could dive into some basic widefield tutorials, that is an entire other article on its own and we’ll talk about it in the coming week.
• Prime Focus astrophotography:
  Prime focus is where you really start venturing into proper astrophotography. It involves attaching a camera(almost always a DSLR, as it can easily be attached and removed) to an astronomical telescope, which now acts as the camera’s lens, so to speak. It involves quite a few procedures: one of which is taking multiple photos of the same object and “stacking” them later in software, to get the most detail out of a said image.
  Prime focal astrophotography is also equipment intensive: you need a good DSLR(or in most cases, a CCD imager), telescope, a mount that can hold both objects, some sort of tracking to compensate for the Earth’s rotation, and guidance computers, etc if you want to get really fancy. For this reason, it’s a field very few venture into. This method also takes a lot of time, like I mentioned. Prime focus usually also needs a laptop for remote guidance, much more darker skies than usual, and hours and hours of sitting at the telescope. It’s almost a manic addiction(but according to some people we’ve spoken to, better than drugs, apparently!).
  Prime focus is also software intensive like we mentioned. There’s a plethora of software out there, some very expensive, that can cater to very specific needs of photographers

Stars and the 'Milky Way' are seen in the night sky over a camp, in Altyn-Emel national park, in Almaty region, Kazakhstan. Image Credit: Reuters

• Some other forms of astrophotography:
  There are some niche tools or methods some photographers use to capture the night sky. Some of it can be outright simple, some require a lifetime of dedication and money.
  1. Webcam astrophotography: this assumes you are an amateur astronomer and you have a telescope at home. If you do, webcam AP is a simple way of capturing some objects like the Moon and Jupiter. All you have to do is point your webcam at the eyepiece of the telescope and record images or videos. In fact, there is quite an active community for it even these days thanks to legacy driver support for older webcams.
  2. Building a telescope pier and mini observatory: this is among the farthest lengths some people go to get “that” image. While at a very nascent stage in India, people abroad actually do buy a small plot of land, get permission to build an observatory and set up a permanent imaging center that’s very equipment intensive, so that they have a solution to their AP hunger all year round. It’s definitely for people who are into AP as a profession or are incredibly rich(maybe both).