How To Take Photos Of The Stars | Astrophotography Tips
This is a guest tutorial on astrophotography by landscape and nightscape photographer Matt Saville.
Astrophotography has become incredibly popular in recent years, thanks to advances in digital camera and lens technology.
We can now achieve photos of the night sky with stunning clarity, using relatively affordable equipment! This is something that was barely possible on very expensive equipment a mere 15 years ago.
This article will include astrophotography tips for both beginners and advanced photographers.
I’m going to keep it simple and show you how to capture stunning astro and nightscape images, without spending a fortune or getting a degree in astrophysics.
Don’t worry – I won’t be recommending only the most expensive equipment, or insisting that you spend dozens of hours in Photoshop learning extremely complicated editing tricks.)
Instead of being intimidated by these things right away, it’s best to let your curiosity and creative passion (and budget) slowly lead you in those directions, after you’ve mastered the basics.
So, let’s dive in! We’ll start with the best astrophotography equipment, including lenses and cameras and other must-have astrophotography accessories.
Then, of course, we’ll tackle the challenge of getting the right exposure and ensuring sharp stars in your images.
Astrophotography | Equipment
It can be intimidating when first considering what equipment to buy for astrophotography and nightscape photography.
Sure, a tripod is a must-have item, and a lens with a fast aperture is absolutely important, but what else do you need?
Which bit of gear should you buy first, or spend the most money on?
First, before you spend too much money on equipment, you ought to consider where your creative passion lies. Are you interested in deep-sky images of galaxies and nebulae?
Or, are you more interested in nightscapes (landscape astrophotography), in which the stars are just a part of the sky in your scene?
Answering these questions will help you decide which equipment to buy.
For example, deep-sky photography will require telephoto lenses, or even a telescope, whereas nightscape photography will require wide-angle and ultra-wide-angle lenses.
Indeed, we’re going to cover lenses first, before camera bodies, because they’re that important!
For this article, we’ll keep our recommendations to lenses which are native to the camera system you may already have. Dedicated telescopes are a topic for another day.
For stunning astrophotography of things such as nebulae and galaxies, a telephoto prime lens can deliver impressive results.
Some of the sharpest lenses in this range include Sigma’s line of Art primes, all of which are ultra-sharp:
If you’re on a bit more of a budget, Rokinon has some fantastic, affordable lenses that work for deep-sky astrophotography, too, especially if you’re able to stop the lenses down ~1 EV:
Of course Canon, Nikon, and Sony all have great fast-aperture telephoto lenses. However, most of them are optimized for general photography, such as portraiture.
Although they’re also good at astrophotography, they’re much more expensive.
So, when considering a name-brand lens, keep in mind the other things you shoot besides astrophotography.
If you decide you’re more excited about landscape astrophotography, also known as nightscape photography, then you’ll be looking for 14mm, 20mm, 24mm, and 35mm lenses.
Almost any lens with a fast aperture, whether prime or zoom, is a good choice.
In fact, most wide-angle lenses made in the last 5+ years are very sharp; it is only in the extreme corners of wide-angle lenses that we see significant differences.
The “nifty 14” of ultra-wides, the Rokinon 14mm f/2.8 UMC, is a great beginner lens for astro-landscape photography.
It offers a good focal length for both full-frame and crop-sensor camera bodies and is available on literally every camera system.
Alternatively, Rokinon has two newer 14mm lenses which may be perfect for you depending on your other needs. You can read about them in my full Rokinon 14mm comparison.
There are a lot of great f/2.8 zoom lenses which cover 14mm, 15mm, or 16mm. However, they’re a bit more expensive and heavy.
If you’re OK with this, then great landscape-astrophotography zoom lenses include:
Don’t forget, of course, the various wide-angle f/1.4 primes which offer both incredible light-gathering ability wide-open, and incredible image quality when stopped down.
There are innumerable primes in the range of 20mm to 35mm. Some are f/1.8, some f/2 or f/2.8.
Each of these can be a good choice, but they’re usually a compromise that you would make based on the other types of photography you shoot, besides nightscapes.
Camera Bodies for Astrophotography
Many experienced photographers recommend only the expensive, full-frame cameras for astrophotography.
The most important part of the equation is not the camera body! Yes, it’s the lens, but more importantly, it’s the techniques used.
With that in mind, any interchangeable lens camera body made in the last few years will do a great job, as long as the lens on it is fast and sharp.
This means that any full-frame camera will work great. Further, any APS-C (1.5x and 1.6x) crop sensor camera body will work great if you have an f/1.4-2.8 aperture lens.
You can even get great results with some of the latest Micro Four-Thirds camera bodies, as long as you have a fast, sharp lens and the right technique.
Of course, everybody loves actual recommendations! So, here’s a quick list of some of the best full-frame and APS-C camera bodies for astrophotography and nightscape photography:
Astrophotography Modified Cameras
Should you get a dedicated astrophotography camera? There are a few cameras on the market, such as the Nikon D810A and the Canon 60Da, which have a specially modified sensor which is optimized for seeing the night sky.
Alternately, you can get an ordinary camera modified for astrophotography.
These cameras allow you to capture better image detail from certain wavelengths of light (Hydrogen-Alpha, for example) which are barely visible or even invisible to the human eye but are beautiful parts of our universe.
Do you really need one of these cameras? If you’re serious about astrophotography, it’s definitely something to consider.
However, for anyone who also does any amount of traditional photography in the daytime, an astro-modified camera won’t be optimal.
Therefore, it should usually be a 2nd camera. Otherwise, all your images in daytime will have a faint color cast or misrepresentation.
You can try to correct for this with white balance tweaks, but it’s not very practical, and never truly perfect.
Do you Need A Tracker For Astrophotography?
If you’re interested in deep-sky astrophotography with telephoto lenses or telescopes, then one of the most helpful, even critical tools will be what is known as a tracker.
This is an accessory that mounts on your tripod and slowly moves your camera and lens to match the earth’s rotation.
This allows you to shoot very long exposures of the stars without them blurring into star trails! (See “The 500 Rule” below for more information on avoiding star trails.)
There are a few basic star trackers that are relatively simple, portable, and affordable. The most popular models are the iOptron SkyTracker, the SkyWatcher Star Adventurer, and the Slik Astro Tracker.
By the way, even if you do nightscape photography with a wide-angle lens, you can still put a tracker to very good use.
What most photographers do is capture one image while the tracker is running to get a long exposure of the sky with pinpoint stars.
Then, they capture a second image while the tracker is turned off to get sharp detail in the earth beneath.
Finally, they simply open the two images in Photoshop and layer mask them together to reveal perfect detail in both the sky and the earth.
Tripods for Astrophotography
Literally every exposure you ever make in astrophotography will be measured in whole seconds, and will therefore require a tripod.
Buying the lightest, cheapest tripod you can find is simply a bad idea! You want a heavy, strong tripod that resists things like bumps and wind.
The good news is that such solid, strong tripods can be quite affordable. (You can still have your lightweight travel tripod as well!)
Alternatively, many great tripods can be found used, such as those by Manfrotto or Slik. If you have a little more money, used Gitzo tripods are impressively stiff.
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Reflection Canyon Camping and Milky Way #timelapse. This is what the last year of my photographic endeavors have built up to. #ReflectionCanyon is a wilderness destination very far off the beaten path, and seen by very few people. The sight was truly memorable, and I would love to return some day for clearer skies…
There are innumerable tripods that I could recommend, and there are even more tripods that I could warn to avoid because they’re junk. To keep it simple: avoid no-name, generic, or low-budget tripods.
This includes even some of the recently popular brands which come in different colors; they are unfortunately not very stiff at all, and rather prone to breaking.
So, stick with name-brands which have been around for many years, no matter what.
You don’t have to break the bank to do this, and it could save your camera and lens from catastrophic damage.
Useful Accessories for Astrophotography
There are a whole lot of fancy accessories that you can buy for astrophotography. Just keep in mind that they aren’t truly crucial for good star photos, although they can help you elevate your game for relatively little cash.
The handiest and most affordable accessory is a cable release. Having one will allow you to click all your exposures without bumping your camera and tripod, ensuring better sharpness.
Of course, if you don’t have a cable release, you can always use your camera’s built-in 2-second timer or exposure delay mode.
Besides a simple cable release, an interval timer is another accessory which can be very useful for creating nightscape images and timelapse videos, if your camera doesn’t have the capability built in.
Instead of just having a single shutter button, an interval timer (intervalometer) allows you to capture multiple photos at set intervals. It even lets you pre-program a long “bulb” shutter speed if necessary.
One last accessory that can be useful is a light pollution filter, which as its name implies is meant to cut out light pollution from night skies and reveal clearer detail in the heavens.
The effects of such filters can be significant when shooting in light-polluted cities.
Depending on what types of celestial objects you want to “image”, a common filter to consider is a “narrowband” filter, which suppresses the light from both sodium and mercury vapor street lamps.
You might instead want a “broadband” filter for conditions where light pollution is less but still present.
Astrophotography | Camera Settings
The learning curve for astrophotography and nightscape photography can be steep.
However, once you get out there and break the ice, any initial confusion or intimidation will fade quickly and you’ll start getting impressive results in no time!
That is, of course, if you remember which exposure settings to start with, and how to dial them in perfectly every time.
Here’s the basic premise of the secret to a correct astrophotography exposure: Firstly, never trust your LCD.
You’ll be outdoors in a very dark environment, and your LCD will fool you every time, even if you turn it down to its dimmest brightness setting.
Check your histogram every single time! However, a “correct” histogram of a night sky isn’t the same as what constitutes “correct” in the daytime.
ETTR (Expose To The Right) doesn’t apply perfectly to astrophotography, due to how much near-black sky is in your image compared to how tiny the actual stars are in your shot.
In fact, if you “ETTR” a night sky too much, most stars will turn to pure white, instead of showing their subtle colors, and things like planets and galaxies will really blow out to white.
A “correct” histogram may be 1-2 EVs under-exposed. With that in mind, where should you start? A fast aperture, a very high ISO, and a shutter speed measured in whole seconds, not fractions of a second.
For your first test exposure, use the fastest aperture your lens has, and an ISO that is a stop or two higher than you might usually use.
This will allow you to check your histogram with a 1-4 second exposure, instead of waiting around for 15-30 seconds only to discover that your exposure was way off.
(Or, just disregard this advice if you have a lot more patience than the average young adult these days!)
Okay, let’s say you start at 1 second, f/1.4, and ISO 6400. Depending on if there’s any moonlight or light pollution, your histogram might be off by a few stops, or just one.
Then, let’s say you adjust your shutter speed to 4 seconds, and your histogram looks perfect!
If your test exposure has an ISO or aperture that you’d usually not use, then just use the exposure triangle to get to your optimal settings. For example, 4 seconds, f/1.4, and ISO 6400 is the same as 15 seconds, f/2, and ISO 3200.
(To be completely honest, I do these calculations quickly in the field by counting on my fingers. Hey, it works!)
The 500 Rule
Before we go further, however, there is a problem with longer shutter speeds. Fifteen or 30 seconds sounds like a totally acceptable shutter speed for nightscape photography, but we have to consider the earth’s rotation.
Simply put, if your shutter speed is too long, stars won’t be pin-points anymore. They’ll be star trails. Unless you’re intentionally trying to photograph star trails, you’ll have to use a shorter shutter speed.
Unfortunately, a “safe” shutter speed isn’t just one number. It depends on how wide (or telephoto) your lens is.
A very wide lens can use longer shutter speeds without revealing star trails, but a telephoto lens will show star trails even at relatively short shutter speeds.
The good news is, there’s a simple rule you can use to get the right shutter speed.
It was first commonly known as the 500 rule: Take the number 500, divide it by your focal length, and that will give you the shutter speed in seconds.
Say for example you have a 14mm lens: 500/14=35. So, 35 seconds could be an acceptable shutter speed.
The bad news is, this rule only works if you’re just sharing your photos on social media in low resolution, such as on Instagram or Facebook.
If you’re going to make very large prints with your images, the 500 rule is obsolete. Especially if you have a 24-50 megapixel camera, you’ll want to use a slightly faster shutter speed.
Some people use the number 200 or 300 instead of 500, but personally, I find the number 500 easier to remember.
I just take that shutter speed, (say, 35 seconds) and I go one stop faster, or just a bit more (~15 seconds). This may sound like a rough generalization, but it works very well!
When in doubt, simply zoom in to 100% and review your images, and see if the stars appear as lines or dots.
Astrophotography | Focusing On Stars
Okay, now that we’re truly ready to take pictures, let’s talk about one of the most important factors, and something that causes trouble for beginners: focusing correctly on the stars.
Let’s make absolutely sure that the focus is perfectly sharp. First and foremost, does your lens have an infinity mark? Start there, but keep in mind that it’s just a starting point.
Perfect focus for stars could actually be just to the left or right of the infinity mark on your lens.
Unfortunately, if your lens has no infinity mark–and especially if the focus ring is electronic–you’ll have to start from scratch every time.
Use live view, magnified to 100% over a very bright star or planet in your image, and then set focus manually.
Rack focus back and forth a whole bunch until you have a good idea what the sharpest, most pin-point stars look like, and then dial that in very carefully.
If you don’t have an f/1.4-2.8 lens, or if your camera sensor produces a lot of image noise, then it may be impossible to even see most stars in live view.
You’ll have to re-compose your shot completely, and point your camera at a bright planet or a distant light on the horizon, set focus, and then re-compose your shot without bumping your lens or accidentally triggering autofocus.
By the way, yes, some of the latest cameras might be able to autofocus on stars. However, it is still very useful to know how to focus manually on stars, just in case you find yourself in a situation where autofocus lets you down.
Astrophotography | Conclusion & Checklist
Hopefully, you’ve found these tips for astrophotography useful! Any time of year, during any season, the night sky can offer beautiful subject matter for many different types of photography.
In summary, here is everything to remember when you go out, whether it’s your very first time in the field or your tenth:
- Make sure you have a sharp, fast lens, at whichever focal length suits your creative interest.
- Almost any current-generation camera will do; pick your camera system based on all the types of photography you shoot, not just astro.
- Use a strong, reliable tripod, for optimal image detail and the safety of your gear.
- Always use a cable release or exposure/mirror delay mode, and electronic shutter if your camera has it.
- Shoot a test shot with your fastest aperture, a very high ISO, and a 1-4 second shutter speed.
- Check your histogram every time; never trust your LCD brightness. Turn down your LCD brightness to help preserve your night vision.
- Focus carefully, re-focusing as many times as necessary until you’re absolutely certain where perfect focus is.
- Check your shutter speed to make sure that stars are not “trailing”.
If you found this tutorial on how to take photos of the stars helpful, check out my complete workshop on SLR Lounge: How To Photograph the Milky Way.
It dives even deeper into each of the subjects covered here in this tutorial, and includes extensive post-production video tutorials as well.
Disclaimer: All recommendations are impartial and based on user experience, with no bias to the products or the brand. The products in this post may contain affiliate links.