Photographing Meteor Showers

The key to making great photos of meteors is to be real quick with the camera.

Just kidding!

Actually, the real key is to be slow and methodical. As in taking your time to set up and get everything just right. The idea is simple. Point the lens at a section of sky where you think (hope) a meteor will occur, lock down the shutter to shoot continuous exposures, then cross your fingers for a flash of light. How well you execute the process will determine success as much as whether or not you see any meteors.

First, find a dark location, as far away from city lights or other light pollution as you can get. You may see very bright meteors in a light-polluted sky, and if that is your only choice, go for it. But to see the most meteors, dark skies rule. This goes for light pollution from the moon, as well. While you can’t escape moonlight by driving, you can lessen its impact by shooting in the opposite part of the sky. Also, the lower the moon is in the sky, the less light pollution it causes, so make sure to shoot as much as you can during these times if the moon is out.

Two Perseid meteors in the night sky beside the Milky Way
A pair of Perseid meteors streak across the sky beside the Milky Way. I photographed this scene in western North Carolina during the 2012 Perseid meteor shower. Nikon D700, Nikon 14-24mm lens, ISO 1600, f/2.8, 25 seconds.

All meteor showers have a radiant, which is the point in the sky from which the meteors appear to emerge. If you trace the streaks of light backward, they all lead to this point. Meteor showers are named for the constellations or brightest stars that lie nearest this point.

You might think that the best direction to point the lens would be the radiant, but that is not so. Meteors can appear anywhere in the sky when the radiant is above the horizon. With most showers, you’re just as likely to spot a meteor away from the radiant as toward it. In fact, you may see fewer meteors if you look toward the radiant. Looking in that direction, some of the meteors you see will be coming at you head on and will not produce long streaks of light. But if you look at a right angle to the radiant, the meteor streaks will cover a longer portion of the sky. Really, the best approach is to choose the direction based on light pollution and compositional elements.

There are two basic approaches for photographing meteor showers. You can shoot a star trail sequence that has meteors streaking across the star streaks or you can shoot a static star scene.

For star trails, you’d set it up just as you would any star trail scene and hope that some meteors occur during the sequence. With the camera mounted on a sturdy tripod, shoot continuous exposures and stack the frames in the computer to create the final image. My base exposure for star trails is f/2.8 or 4, ISO 400, and 4 minutes. Do a test to make sure the exposure is not blown out by light pollution, and then adjust as needed. You can record more stars if you shoot at higher ISOs, but you may have to shorten the shutter speed to keep from overexposing the sky. At higher ISOs, you get more noise, and the signal-to-noise ratio comes into play. For instance, at ISO 1600 and 30 seconds you might be gathering a lot more noise compared to the signal (the light you want to record) than you would at lower ISOs and longer shutter speeds.    

I typically prefer to photograph meteors as part of a scene where the stars appear as pinpoints of light instead of streaks. The meteor streaks contrast with the pinpoint stars, acting as strong components of the composition.

For the most effective compositions, you want to compose a scene that works well without meteors. Ideally, you want some sort of foreground element in the scene, instead of just a bunch of stars. But remember, you want to include as much sky as possible to increases your chances of capturing a meteor, so choose the foreground carefully. An ideal foreground is one that looks good in only the bottom one-sixth or so of the frame and has an interesting top line, like a jagged mountain range.

A Perseid meteor shines in the night sky with the Milky Way
A bright Perseid meteor shines through the clouds during the 2012 Perseid meteor shower in western North Carolina. Nikon D700, Nikon 14-24mm lens, ISO 1600, f/2.8, 25 seconds.

If the foreground doesn’t work as a silhouette against the sky and if it is close enough, you can light paint it to make it stand out. Shine a flashlight or pop a flash on it. You can get creative with choosing foregrounds to light paint. Campsite scenes with lighted tents are always a good choice, but anything that you can throw a little light on is a candidate.

If the foreground projects far up into the sky, it should be one that has graphic lines that work well as silhouettes and something that doesn’t have a lot of mass so some of the stars will show through. Bridges, towers, isolated trees, lighthouses, and similar subjects all work well.

Whatever you choose as the foreground, make sure it is far enough away that you can shoot wide open and still have enough depth of field so that it, and the stars, are in focus. For a wide-angle lens, that point may be closer than you think. With a 17mm lens, you have depth of field from about 10 feet to infinity at f/2.8. With the 14mm lens I often use, DOF is from 6 feet to infinity at f/2.8. But I don’t like to cut it that close. To achieve the full DOF, you have to focus precisely at the hyperfocal distance, which isn’t the easiest thing to do at night. I typically like to have the foreground at least 25 feet away, and even farther is better. That way, I can focus precisely on the foreground, knowing it and the stars will be sharp. Of course, I always check for sharpness in both the foreground and the stars before letting the camera run.

In addition to choosing a good foreground, you should pay attention to what’s in the sky. Try to use prominent constellations or star patterns, such as Orion and the Big Dipper, as complementing elements. If there are any bright planets visible, try to incorporate them. The Milky Way is always a strong compositional element.

Once you set up the composition, the exposure for a static star scene will be the same as on any other night. Assuming a relatively dark site, the main consideration will be shutter speed, because at a certain length the stars will begin to streak. For this reason, as well as for making the best compositions that increase your chances of capturing a meteor, a wide-angle lens works best. I should point out that the wider the lens, the fainter the meteors record. So while a very wide-angle lens increases your chances of capturing a meteor within its field of view, if the meteor is very faint, it will not show up well in the photo. Still, I prefer to cover as much sky as possible with the composition.

To determine the point at which stars appear to show obvious streaks, divide the focal length of the lens into 500. So for a 17mm lens, you can get by with about 30 seconds. This is just a general guide and it depends on the direction in the sky that you shoot. (The stars will appear to streak more when shooting toward the south, and if you magnify the image, you can see streaks after only a few seconds with any lens.) Since it isn’t precise, and since 30 seconds is the longest shutter speed that my camera allows without using the Bulb setting, I typically shoot night sky scenes at this speed with focal lengths from 14mm to 18mm.

Set the aperture wide open or close to it. For most lenses, this will be f/2.8 or f/4. The only reason not to use f/2.8 (or wider if you’re lens offers it) is if your lens suffers from coma, a lens aberration that causes stars to record as little snow angels instead of pinpoints of light. Coma is reduced as you stop the lens down. Even the difference between f/2.8 and f/4 can be significant, and by f/8, it is usually not noticeable. My Nikon 17-35mm lens has horrible coma, so I never shoot it at f/2.8. Actually, I rarely use the lens for night photography anyway, much preferring the Nikon 14-24mm.    

Try ISO 1600 as a starting point. Do a test exposure and see how it looks. If there is a lot of light pollution in the sky, you might have to back off a little. At a dark site, you can definitely shoot 30 seconds at f/2.8 and ISO 1600 without any problems. If your camera doesn’t have a lot of noise, you can shoot at even higher ISOs.

Once you get the composition and exposure set up, set the shutter to shoot continuous exposures and just let it rip. With a locking cable release, you can set the shutter dial to shoot continuous exposures and then walk away and let the camera do all the work. Most Nikon (and Canon, too, I think) cameras only allow you to shoot 100 exposures this way. To shoot more than 100 shots at a time, you have to use an intervalometer, either an external one like the Nikon MC-36 or the Canon TC-80N3, or, if you’re a Nikon shooter, the internal one that’s accessed in the menu. Note that the built-in timer will only allow you to shoot exposures up to 30 seconds long. If you want to go longer, such as when shooting star trails, you have to use an external intervalometer.

(Just let me catch a Nikon suit in a dark alley. I’ll get us that simple firmware upgrade that would give us built-in shutter speeds longer than 30 seconds!)

Of course, it’s a simple matter to shoot 100 exposures and then start the sequence again. In fact, you probably don’t want to shoot more than that at a time anyway, because during those 50 minutes the stars will have moved a considerable distance in the field of view. If you compose the scene to take advantage of constellations, you’ll have to recompose periodically throughout the night.

So you can see that there isn’t anything all that different in shooting meteors than in other types of night-sky photography. Composition and exposure is pretty much the same. The idea is just to shoot a lot of exposures and cross your fingers.

Hope you catch a falling star!

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