Here are two popular methods for doing amazing star trail photography. The first is the recommended method to get the highest quality image, but method two can also be used.
Using Multiple Exposures for Star Trails Photography
The reason why the first method is the best option is that the multiple exposures enable you to keep the exposure time and ISO on the low end. These are night photographs, so that helps tremendously in reducing noise. Almost every camera will exhibit exposure noise when it is pushed to a very long exposure (over 3 minutes).
Although many cameras have what’s known as a Long Exposure Noise Reduction (L.E.N.R) setting, it does not work quite as nicely as using the first method with multiple exposures.
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Method #1: Stacking Star Trail Photos
This preferred method can be used to capture beautiful, high-quality star trail photos with the use of multiple exposures. Each exposure will capture small star trails and you will capture more as time elapses. You will use the exact same camera settings for each exposure, and you will overlay them later on to get the full effect. The only thing that will change between exposures is the stars’ positioning relative to your location on Earth.
“Keep your eyes on the stars, and your feet on the ground.” – Theodore Roosevelt
You’ll batch process these photography images in Adobe Camera RAW or with the use of Adobe Lightroom. You will then import them into Photoshop where you will process them together.
The key here is deciding on the number of exposures. Your location, your lens, your camera model, the composition, and your desired effect of either short or long trails will affect how many exposures are required. That means it is not possible to provide an easy reference chart with numbers.
Truly, the only way to perfect your star trail photographs is to go out and begin taking practice shots to see what gets you the desired results. The number of exposures necessary will be in direct correlation to the percentage the composition takes up of the night sky.
As an example, if your composition is half foreground and half sky, your stars will move across half of the photo to produce the star trail. If your composition is 3/4 foreground and only 1/4 night sky, the stars will move across a quarter of your photo. This means less time will be required to shoot the star trail, which means fewer exposures.
There are a few ways to calculate the shooting time when you want to photograph star trails:
- You can use PhotoPills as they have a great tool inside the application that enables you to calculate how long you need to shoot to capture a star trail in a specific composition.
- You can also set up your camera and use a timer. Let the timer run for 3-4 hours. This will capture enough exposures regardless of your composition to produce some beautiful star trails. You’ll end up with many more than required, which lets you pick and choose.
- Finally, you can use the simple trial-and-error method. That means taking multiple photographs of star trails using different compositions and different lenses to get a better idea of what works and what doesn’t. This is definitely the most time-consuming method, but also the most effective.
When it comes to choosing the timer settings on your camera, a camera timer or intervalometer is definitely recommended. Without one, you will be pushing the shutter button repeatedly for hours on end. Most cameras have an interval timer mode that is built directly into them and works well for star trails photography.
Once you have determined how much elapsed shooting time is required for your composition, you just need to adjust your camera’s timer so reflect your calculations. You should input these settings into the timer:
- The length of each exposure. For example, you might need an exposure time of 23 seconds.
- The time between each exposure. Typically, 1 second is a good setting. That means the camera takes a photo, waits a second, and then starts to take the next photo.
- The total number of exposures required. This is the total amount of time that your camera will be taking photos or the total number of photos you want your camera to photograph. For example, you might tell your camera to take 100 exposures at 23 seconds each with 1 second in between.
These are all dependent on one another. Once you calculate what’s needed, it’s relatively simple to get your camera setup and photograph star trails.
Method #2: Single Exposure
This method uses only a single long exposure. That means your star trail will be captured in a few minutes’ time and, in most cases, it’s going to lead to extra noise that can lower the photograph’s quality. You also won’t see the star trails transverse the photo’s entire composition. Rather, the star trails are going to resemble long streaks of light that are crossing the sky.
“Set your course by the stars, not by the lights of every passing ship.” – Omar N. Bradley
Photograph Star Trails by Using Single Exposure
If you want to try this method, follow these steps:
- Turn on the L.E.N.R. setting on your camera, or the Long Exposure Noise Reduction setting, as this will help improve the quality by reducing the noise. This setting can be located by checking a tutorial for your camera model online or looking at the instruction manual for your camera. Most cameras have these settings, especially full frame cameras.
- Once you have turned on your L.E.N.R setting, you will want to focus your lens.
- Now, select a composition. You should try to get an exposure time of 3-4 minutes. Use an ISO of about 600 to 800 and take a photograph. This involves some trial-and-error. If the photograph turns out to be too dark, you’ll want to increase the exposure time. The trails are not long enough, increase the exposure time some more. It’s really a matter of personal preference.
- As required, go through and decrease/increase your ISO based on the noise you see in it.
This method requires some practice to see which settings get you the best photos. When possible, use method one for the best overall results.