how to shoot star trails
Star trails photography is one of the most popular photography techniques in the field of night and landscape photography. Pictures of star trails are incredibly interesting and eye-catching, especially when combined with attractive foregrounds. How is it done? What is the recommended equipment? What is the correct technique? All the answers and more in this article!
Star trails at DeadVeli, Namibia
what are star trails?
Before we start talking about equipment and technique, let's understand what it's all about! I'm sure none of you have ever seen star trails when you looked up at the night sky, right? Star trails is a photography technique that allows us to see the orbit of the stars in the sky during the night. Moving stars? Yes! The stars move during the night just as the sun and moon move. Actually, the stars do not really move… planet earth rotates on its axis and that's what makes the stars "move" in the sky. With the help of the photography technique we will talk about later, we can create an image that shows the continuous movement of stars in the sky.
recommended Gear to shoot star trails
Very simple - a camera with manual exposure control, a wide angle lens, a tripod and a remote control that allows you to shoot continuously (it can be a simple remote, an intervalometer remote or an internal intervalometer in the camera). It is also recommended to have a fully charged battery and a memory card with enough space for several hundreds of photos.
star trails photography technique
In the age of film before digital cameras, shooting star trails was done by a single very long exposure during the night (a few dozens of minutes to a few hours). As the stars "move" in the sky during the night, it obtained an image that showed their orbit. This technique is still possible today even with digital cameras, but the more common technique is to shoot a continuous sequence of frames during the night and then to combine them in an editing software to create the star trails. The main reason this technique is more common, is because it allows you to delete a certain image from the sequence, if for example someone accidentally entered the image or turned on a light that you would not want in the final photo. Two other advantages of this technique are that you can use each individual frame from the sequence as a night shot, and also that you can use the same sequence of images to create a time lapse.
exposure settings for star trails
Before we even create an image of star trails, we need each image from the sequence to be an image with proper exposure for night/astrophotography. Generally, in order to achieve a well exposed image at night we will use high ISO, relatively open aperture and long shutter speed (long exposure). I won't go into details about it in this article, as you can read a detailed and full article about it in my article about "Landscape night photography". The article also explains the challenges of depth of field and focus during night photography and how to overcome them, and recommendations for creating compeling compositions.
Night shot of Mount zin and the Bulbus field in the Israeli desert
other settings for star trails
After setting the exposure, focus and composition we basically want to make the camera shoot images continuously (the shutter speed of each frame will be between 15 and 30 seconds approximately) for a few dozens of minutes or a few hours. The longer we take pictures during the night, the longer the star trails will be. In order for the camera to do this, you will need to set it in continuous shooting mode (regardless of whether it is fast or slow) and connect a remote control that "holds" the exposure. I really like and recommend using a wired remote as they are more durable and work even without a battery for holding the exposure. Those of you who have a camera with a built in Intervalometer can use it to make the camera shoot continuously.
which direction should you shoot?
Star trails can be photographed in any direction - the question is what you want to achieve and what you prefer. If you are in the northern hemisphere shoot the sequence to the north, you will get star trails in the shape of a circle - because the earth rotates on it's axis in the direction of the north star (Polaris) while all the other stars "rotate" around it. If you shoot east or west you will get relatively vertical trails (sometimes parallel). If you shoot south you will get half arches (similar to arches of northbound photography, but without a circle and a fixed star like the north star, since you are in the northern hemisphere). If you are in the southern hemisphere - everything is the same, just the opposite.
Circle shaped Star Trails - shot to the north (northern hemisphere)
Arches shaped Star Trails - shoot to the south (northern hemisphere)
Short technique summary: you arrived to a beautiful place at night, found an interesting composition and thought about the kind of trails you will get according to the direction and the foreground composition, you mount the camera on the tripod according to the composition, set the exposure settings, focus according to the hyper-focal distance, make sure the camera is in continuous shooting mode, connect the remote and hold exposure, wait a few hours and you're done! While the camera is doing it's magic, I recommend enjoying a good coffee, beer, friends and the night sky!
what do we get
After the session ended, you will have a memory card with several dozens or hundreds of images from which you can edit and create the image of the star trails, for example:
The next step is to create the Star trails image! It is highly recommended to post process the sequence of photos you have (edit one photo and synchronize to the rest). We will then save all the photos in the sequence as JPEG images and transfer them to a software that creates an image of star trails like "StarStax". Star trails softwares create an image by stacking the sequence of images, with each image adding information only if there was more light in it. So basically each image adds stars in a slightly different position according to its orbit and an image of the trails is created!
Star Trails photography is extraordinarily fun, with the potential for beautiful results! In order to get the best results, it is important to choose good locations, imagine the frame you want to achieve and plan everything in advance in terms of shooting times, moon lighting, the surrounding landscape and the composition. As you practice more and more practice, the process will be more comfortable and easy 🙂