Star Trails
Capture the movement of the stars through the night sky with a series of long exposures that turn these pin-pricks of light into elongated streaks
Now that we know about the 500-rule and how it allows us to shoot stars without motion, it’s time to break that rule. Star trail photos can look incredible when they’re done well, creating the appearance of a disc of stars. Shooting star trails requires longer exposure times than shooting a static sky. The most effective way is taking multiple images and stacking them in Adobe Photoshop. Shooting star trails in camera is possible, but it’s not going to give us a good contrast in the sky and can result in clipped areas of the image, particularly on the horizon. Even the planet’s dark sky sites will give us light pollution.
Trail and error
We can use a remote shutter release locked to shoot continuously, or we can set our camera to shoot for a pre-determined number of shots. We can set this in the menu of some Nikon cameras by navigating to the Interval Timer within the Photo Shooting Menu. In this menu we set the number of intervals, the number of shots, and the time between shots. We may also notice a Silent Photography option, which is a good idea because it prevents shutter movement and therefore prevents unnecessary vibration in the camera that may disturb our shots.
Avoiding any movement whatsoever when we shoot star trails will give us a consistent image free of any unwanted kinks in the perfect spherical tracks of the stars. For this same reason it’s important that we use a good, sturdy tripod with a solid ball head to keep our camera rock-steady while we’re shooting into the night sky.
Poles apart
The important thing to consider with regard to our composition when we shoot star trails is the direction. In the northern hemisphere, the night sky rotates around the north star, Polaris. To get the classic ‘disc’ look, we need to be shooting towards Polaris, otherwise we get streaks of stars rather than rotation.
The time of night is important to star trail photos. For the most contrast in the stars we should be shooting during astronomical night, after astronomical twilight. Shooting during twilight times can result in nice photos and it can even add a suitable ambience if we shoot in a considered way. A moonless sky will also give us the best results for star trails, as well as for Milky Way photos.
The length of time that we shoot for determines the length of the star trails, and we can use the Photopills app to give us a simulation of the length of the trails based on shooting times. Shooting for more than an hour is often a good idea and, as such, it’s often a good idea to ‘lock off’ our camera in a secure position and leave it while it shoots, coming back to it later. It’s also a good idea to take multiple batteries if we intend on creating multiple shots, using one battery per series of shots.