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How to shoot stunning starry night photos


The easy way to shooting stars, planets, night skies and landscapes


Star trails at Joshua Tree

© Dan Eckert

Some of the most interesting features of digital cameras is that they can easily be used for night photography, thanks to their ability to shoot long exposures.
Unlike film, camera sensors do not suffer from reciprocity failure: this means that you can easily take astonishing digital pictures of dimly lit subjects, including night scenes of city skylines, moonlit night landscapes, starry skies, falling stars and more.

Also, you do not need to own an expensive digital reflex: while a good, full-frame DSRL would be the best choice ever, it turns out that also compact cameras can shoot stars with good results.
Here are some night photography tips aimed at star shots.

Before you even start thinking to shoot night sky (and astrophotography in general) make sure that you have clear weather and there is not too much light pollution in your area: you might want to check a dark sky finder and charts (try this) just in case.

First 7 steps in star photography


In order to get the best night pictures under a starry sky, there are a few points to be known.
Let’s see and follow some night photography tips aimed at star shots:

  1. Stars continously move accross the sky (well, obviously it is the Earth that moves, but let’s keep it now at a basic perception level). So, depending on what time of the year and when through the night you look at the sky, you will see the same stars in different positions relative to the Earth. Only the North Star stays still, beeing aligned with the Earth’s axis of rotation (here is why it has been used as a reference point for navigation through the ages) while the whole sky is pivoting around it. Stars are moving faster than you might guess (and the Moon as well, as we’re here). The fastest ones are those placed farther from the North Star.
  2. Place your camera on a solid tripod and point your lens to the sky. You cannot handheld when shooting stars: either you keep your camera steady on a tripod or you rig it to some special kind of gear allowing it to track and follow (replicate and so visually neutralize) the apparent sky movement as the Earth rotates (this is the way most telescope mounts work, but it goes beyond our primer’s scope).
  3. Carefully compose your picture and focus your subject. Including the Milky Way into your frame would probably add a fascinating factor to your photographs. Focusing in dark conditions is sometimes easier if you place a flashlight next to your subject and focus on that light. Focus on infinite is a no-brainer and suggested choice. It is usually an interesting visual choice to include some landscape elements in your frame. Remember: there is no rule in composition, just taste. As an idea, you could also mostly include static objects into the frame, while leaving only a proportionally smaller area to the sky. There is no such thing as a best focal lenght for shooting skies: you might start with a 35mm lens, which is usually a good choice as a general lens. Also, a standard 50mm lens can be a good choice: it is usually a faster lens, allowing for shorter shots.
  4. Disable any automatic behaviour of your camera (autofocus, aperture, auto-iso, auto-whatever…)
  5. Disable your camera/lens anti-vibration mechanism. This is usually named VR (vibration reduction) by Nikon, IS (Image Stabilization) by Canon, SR (Shake Reduction) by Pentax, SS (Steady Shot) by Sony, and so on. Actually, some cameras (like Pentax K-5 and K-r) can use their sensor-shift capability to reduce star trails, so, as always, read your manual before using your camera.
  6. Set image format to Raw (you should always shoot Raw, actually). If you have problems with Raw (i.e. your camera cannot shoot Raw or it takes too much time/memory/effort to handle Raw) just stick to Jpeg.
  7. You might want to set aperure to its fastest selection, that is the lowest number available, and the widest aperture for your lens.

You’re almost done.
Now let’s go for the most challenging choice!

Standard look vs. Star trails

Magellanic Clouds

Original images © Alex Cherney

You are now ready for your shots, but there is one more key step to consider.
Basically, you can attain two very different results when shooting stars:

  • You can get a classical rendering of the sky, where everything appears to be in its own place, sort of the way we see things as we stare at the night sky.
  • Or, instead, you can have an astonishing set of star trails, which all appears to revolve around the North Star (or the southern celestial pole, alternatively), contrasting with the landscape elements (which remain steady in your frame). This is generated by a very long exposure time setting (in the range of hours) or better by a composed bunch of shorter shots.

Astronomers are obviously more inclined to prefer the fixed stars approach, whereas from a pure aesthetic point of view star trails may appeal to general photographers because of their amazing whirl and surprising look.
Let’s see them both here below.




How to shoot stars with a steady look

See a wonderful video of stars and lanscapes at www.timescapes.org (full screen) © Tom Lowe


Due to Earth rotation, each star will end up drawing a short line across the sky: such lines will be more evident:

  • the bigger your image final enlargement
  • the longer your focal length
  • the longer you keep your shutter open
  • the bigger the star (apparent) distance from celestial pole

Avoiding star trails is basically a matter of matching all the four points above.
As a rule of thumbs, using a wide-angle lens with an exposure time of 15 seconds should not show too much of a star trail on average, provided that you enlarge your picture at a standard size, let’s say at about 10 inches wide.
For pin-sharp stars keep exposure time low: make a couple of test shots and see them enlarged 1:1 to properly judge.

Now:
  1. Set Iso to normal or slightly more than normal, but avoid high sensibility. Too high Iso values amplify noise and degrade image quality. Let’s be clear and honest: better pictures are given by not so high Iso settings, but what we’re trying to do here is to easily record stars. Once you will get enough experience and excitement with your images, there will be time to improve you technique. For the moment, though, feel free to adopt middle-high Iso settings if you see fit.
  2. Proper exposure should be set by changing time: make some test yourself, starting from a few seconds and doubling exposure every new step. The goal is to get the more stars you can.
  3. The best approach is multiple image stacking, that is: take multiple images and layer them one on top to the other. Thus, once you find the right exposure, take a sequence of shots: try 5, 10, 20 of them, as a start. Trigger the shutter by means of a remote release or, in case you do not have one, use the camera self-timer.
  4. Carefully inspect your shots and take some more, with some variations as you see fit.

Image Processing

Once you go back home with your shots, you will need to edit them in order to squeeze the best from their pixels and get really eye-catching final pictures.

You need some software to apply deconvolution algorithms, stack and align all your pictures, thus generating a single, bright, crisp photograph.

Stacking 15 images without (left) and with (right) software processing


General, free picture editing software like Gimp could effectively be used for your goal, but consider it a very labor intensive task.
In order to deconvolute short star trails (eliminate trails due to slightly long exposure times) Refocus or Refocus-it are useful plug-ins, as well as other filters and editing tricks, while stacking and aligning can be done straight with layers.

Alternatively, free specialized software like DeepSkyStacker, Iris, RegiStax (and a bunch more, like StarStaX in case you are on a Mac) can do all the work for you. Such programs are not so easy to use, but produce high-quality, professional results.

See a wonderful video of stars and lanscapes at www.timescapes.org (full screen) © Tom Lowe





Shooting star trails


Any fast-moving source of light (or light-reflecting surface) moving across your frame while the shutter is open will leave a blurred trace of its presence into your picture.

This is no news and you can see tons of such pictures with cars, handheld flashlights, fireworks and more.
After all, photography (from Greek φῶς [phos] “light” and γραφή [graphé] “drawing”) is drawing with light, really.
You should try them by yourself: basically, long exposure times coupled with any moving light will generate a trail.

progressive stacking

Trails generated by progressive stacking

Not everybody knows that right the same effect applies to stars (which should be obvious, after all).
The peculiar fact with stars is that they all appear to revolve around the North Star.
Every single star traces a circular arc where its radius is given by its apparent distance from the Pole Star and its length on your picture depends on both radius and how long your exposure is. Keep in mind roughly 15 degrees/hour, that is it takes 6 hours for a star to paint a quarter of a circle on the night sky.

Star trails are rather easy to attain: follow right the same steps you find in the standard-looking sky section.
Quite simply, you have to keep trails, so no more bothering about exposure times: you can shoot a sequence of how many photographs you like, each one in the range of 1–5 minutes (as a starting test).

Do not forget, at the very beginning and at the very end of your series, to shoot a couple of variations of the foreground objects (say, you might try with and without a flashgun).

Image processing is done again with about the same software tools, just keeping and enhancing trails instead of avoiding them.

Star Trail at Sherborne Castle - England

160 x 30second exposures = 1hr 20mins at f/4.0 and ISO 800 edited with Photoshop © Rich Grundy





Meteors photography

Falling star

© Ed Sweeney Lucky shot at 2:20am at the peak of the 2009 Leonid Meteor Shower Iso 1600, Pentax K20D with an old Super Takumar m42 50mm 1:1.4 open all the way for 6 seconds - click to see uncropped image.


Good luck!

Taking photographs of meteors in not only a matter of having the right gears and enough knowledge for your task: you also need commitment, perseverance and luck.
Be prepared for many hours awake in the dead of the night. Add some warm clothes for you in your bag, plus a couple of old socks to wrap your lens in order to avoid it chilling; extra batteries are also a must.

If you are interested in shooting stars, you might find that the most interesting falling stars shower happens every year, in the first days of August, having its peak on August 12th.
Meteors are mostly to be observed in the second part of each night, that is from midnight on.

North Star and Perseus

Perseus and Ursa Minor with Polaris See bigger

Such meteor shower is actually a stream of debris originating from comet Swift-Tuttle: known as the Perseids (sons of Perseus), they appear to come from the constellation Perseus.
It is there that you should point your camera to.

Perseus is not too apart from Polaris. You find Polaris at the very end of the Little Dipper handle.
If you are not too much acquainted with constellations and the sky in general, you will find it useful and much fun to download and play with http://stellarium.org/ a free open source planetarium running on Linux, Mac and Windows alike. It shows a realistic sky in 3D, with atmosphere, sunrise and sunset effects, more than 210 million stars, the planets and their satellites, and a lot more.


If you like night photography you might well be interested in some of these books:




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