Where should you focus your camera when photographing star trails? The answer might surprise you!
Composition is still king
Like with other forms of night photography, it’s easy to get excited about what is happening in the night sky and forget about composition. But composition is still king.
It’s important to have a strong subject. Whether your subject is a building, car, trees, mountains, a forest, waterfall, or something else, it’s best to have a strong subject. Without that subject, you simply have concentric circles or streaks in the sky.
And like other genres of photography, where do you typically focus? Most likely, you thought, “The subject.”
Focusing on the subject
Focusing on the subject is usually quite simple. You can even use your camera’s auto-focus sometimes. This is done by illuminating the subject with a flashlight, and then focusing. Often, if the moon is bright, you might not even require a light to focus on your subject!
You can also focus by using Live View and zooming in while using manual focus. Or you can lean a flashlight against the subject and manually focus on the light.
Why shouldn’t I focus on the stars?
Most other articles about photographing star trails suggest that you focus on infinity. This is to get the stars in focus. But think about this for a moment. How important is it to get the stars in focus if we are going to do star trails anyway? Focusing on the stars is great advice when photographing the Milky Way. But is it necessary or even wanted for star trails?
Three reasons for not focusing on stars when photographing star trails
- One should focus on the subject, not the stars.
- Stars don’t need to be perfectly in focus if they are photographed as long streaks in the sky.
- Star trails look better when they are out of focus. They look fatter. Also, since they are slightly out of focus, this also hides any gaps you might have between frames if you are “stacking your photos in StarStax or Photoshop. Cool, eh?
A secret star trails technique
If you focus on your subject at about 25-30 feet (7.5 to 9 meters) away, your stars will be more or less in focus anyway. At that distance, after all, you are getting closer to what your lens regards as “infinity.” If you still want your star trails to be slightly out of focus, mask for the sky in Lightroom or whatever you are using to edit your photos. Then pull back the sharpness slider slightly. You can do this to taste.
If for some reason, you really want to have both your subject and stars very sharp, try to make sure that you are at least 25-30 feet away, maybe even more. And if you want to learn how to focus on the night stars, then have a look at this article!
