What do I need for astrophotography?
Astrophotography (photographing the stars) is a very different style of photography compared to wildlife.
Wildlife photography is about split-second decisions, instincts, and a little bit of luck for good measure. On the other hand, astrophotography requires time, preparation, and perseverance (which can sometimes mean sitting in one place for a very long time!).
Before we even begin to consider our camera settings, there are three other things that come into play: the weather, the amount of light, and the time of year.
- The right time of year
- The moon and other light
- Setting up your scene
- Shutter speed settings
- Aperture settings
- ISO settings
- How to focus the camera
Colder temperatures are often better to photograph stars in. This is because the stars will be brighter, so your camera will be able to capture more detail.
The winter months in South Africa are generally better for practicing astrophotography.
Just remember to wrap up warm to compensate for the lower temperatures. If this isn’t the perfect opportunity to wrap up in a blanket with a hot chocolate – I don’t know what is!
You also need to consider the weather. Not only will your hot chocolate be ruined if it’s raining, your camera will be too. And if it’s cloudy, the stars will not be visible, making photographing them a bit of a problem.
Finally, you need to consider the amount of light, both artificial and natural. You preferably want as little light pollution as possible. Even the smallest light from a nearby building or pathway can have a major impact on your images, so find somewhere devoid of these light sources.
This is why having a torch with you when you head out can become really handy!
Believe it or not, the moon will also make a difference. The smaller it is, the less natural light you have.
Remember, you are going to be working with long exposures, meaning if you have a moon in what you are planning to photograph you will be bleaching out a large proportion of your sky. While this can be creative, you will miss out on those all-important stars!
Once you have carefully selected your location you will need to consider your set up. It is absolutely vital that you have a sturdy and stable support for your camera, preferably a tripod that is easy to work with (you will be working with it in the dark after all).
While the stars are your focus, the foreground subjects can be essential to a successful star photograph.
It provides context. Otherwise it can feel like you are simply looking at lots of dots on a page. My advice is that you try to get as low as possible, with the camera tilted up, and frame your subject with the stars behind.
If you find yourself without a tripod, you can be creative in your camera support; rocks, blankets, and boxes can work just as well. I’ve even used elephant poo in the past!
How do I set my camera for astrophotography?
Now we get into the technical side of things. Camera settings can take a little bit of time to wrap your head around, so let’s break it down a little. Firstly, make sure your camera is in manual mode as you will be taking command of all of your settings.
Your shutter speed controls how long your camera records the light in front of it, and because astrophotography is all about working with low light, this is pretty important.
You will be working with so little light you will most likely need a shutter speed of between 20 and 30 seconds (20” and 30” on your camera, not 1/20 and 1/30). Any longer than 30 seconds and you will start to introduce motion blur in the stars from the earth’s rotation.
These times will vary depending on your focal length of choice.
If you’re photographing wide on 16mm, you can have a longer shutter speed than if you are photographing at 100mm, as the more zoomed in you are the quicker you’ll capture the movement of the stars.
If you’re seeing blur in your photos and can’t understand why, check that your tripod is properly tightened. If it is slightly loose or your camera is too heavy, the camera could slowly move while the photo is being taken, causing blur.
Aperture controls how much light is allowed through your lens. You might think you want as much light as possible to travel through your lens, meaning you want your aperture setting as wide open as possible (small f stop number, eg. f2.8, f5.6), however it’s more of a balancing act.
If you want to photograph a landscape with the stars, an f2.8 won’t work as the depth of field is too limiting.
So, we ideally want to increase our f-stop to something broader, but doesn’t this limit the light coming in? Yes, it does – which is why bright stars and ideal conditions are so important.
Another trick is to merge photos together, which is more common than you’d think. This is done by using an f2.8 and photographing different focal points, at different exposures, and then blending them in post-processing.
This way you get the utmost quality and detail, despite it perhaps feeling a little bit like cheating.
Your ISO controls how sensitive your camera is to the light it is recording. This number will vary from camera to camera based on your other two settings and the noise capabilities of the camera. You may find you have to do a bit of trial and error with this setting.
I personally start on an ISO of 1600 and adjust up or down from there. Just remember, keep your ISO as low as possible but as high as necessary.
You will need to make sure your shutter is set to a timer release. Most cameras will be able to set this to 2 seconds, but depending on your model of camera, you may find you have to set this to 10 seconds. This allows you to push the shutter, and the camera to then take the photograph shortly after to eliminate any chance of your finger moving the camera when taking the photograph and blurring your final image.
For Canon, this can be changed in your quick menu. For Nikon, you can use the timer dial below the dial that changes shooting modes. You can then adjust the amount of time delay in your menu.
How do you focus a camera for astrophotography?
There are 3 options for focusing in astrophotography and people tend to have different preferences:
Using either automatic (remember to switch it into manual focus afterwards to keep your focus where you want it) or manual focus and a torch or spotlight to focus on an area of your foreground (such as a tall tree).
This will keep your foreground in focus but may make your stars a little soft when you zoom in.
Using live view rather than your viewfinder, switching to manual focus and using the magnifying option on your camera, you can zoom in to the stars using a 10x optical zoom to then focus until your stars are as small as possible and therefore as sharp as possible.
This is not a great technique on older or even entry level cameras as it can also magnify the noise making it hard to determine focus.
There are many that say they simply switch their focus to infinity and pull it back a tiny amount to focus.
This only works on lenses that have a focus window in the body of the lens.
If you don’t want to wait the full 20-30 seconds to see your final result (i.e. You just want to check your composition to start with), you can set your shutter speed to 3 seconds (3”) with an ISO of 25600 to check this. You will not have a great quality image, but it can be a great way to quickly compose and check focus.
Astrophotography is made for creativity
That sums up the technical side of astrophotography. However, do not forget about the creative side! Consider using a torch or light source to light up elements of your image. Just remember you do not need to expose your foreground for the entire time you are taking your photograph. A quick sweep can be enough. How long you expose your foreground depends solely on how bright the torch is that you are using. Duller ones will need to light your foreground for longer than brighter torches.
Also consider the angle of your light source. Side lighting will create long shadows and harsher contrasts. Finally, consider what you are lighting. Trees, water, vehicles, or even people. There are plenty of opportunities to be creative with astrophotography.
What I love about astrophotography is the time. I have time to try different compositions, time to try different settings, time to try different creative techniques. I even have time to mess it all up and try again.
Read Brigitte Bernard’s story about how she traveled to Africa to fulfill a childhood dream of seeing a leopard in the wild and got ‘the shot’ while doing it.
Or get your shot while volunteering in Africa for the ultimate trip!