Viewing & Photographing The 2014 Geminid Meteor Shower

It’s time for the Geminids!

The Geminid Meteor Shower ranks among the best meteors showers of the year, producing around 120 meteors per hour in ideal viewing conditions.

This year, the peak occurs over two nights for North American viewers—tomorrow evening through Sunday morning and Sunday evening through Monday morning. The third-quarter Moon interferes somewhat this year, rising at 12:07am (EST) on Sunday morning and at 1:02am (EST) Monday morning.

That’s not all bad news, however. Unlike most meteor showers, which don’t become active until after midnight, the Geminids will become visible soon after nightfall, so you’ll have good viewing on both nights before the moon rises.

A particularly bright Geminid meteor from the 2012 shower lights in the western North Carolina sky. Nikon D800, Nikon 14-24mm f/2.8 lens at 14mm, ISO 2000, 20 seconds, f/2.8.

Meteor showers are named for the constellation or brightest star that lies nearest the radiant, and in the case of the Geminids, that’s near the star Castor in the constellation Gemini. The radiant is the point from which the meteors appear to radiate if you follow their path backward. While it is possible to see some meteors while the radiant is below the horizon, you’ll see most of them when it is high in the sky.

Gemini begins rising above the eastern horizon shortly after sunset and by around 8:00pm(EST) it is high enough for good meteor viewing. So this leaves you with several hours of moon-free viewing on both nights. You’ll see more meteors the higher Gemini rises in the sky, but the ones you see early on will be so-called “Earth-grazers,” which display long streaks low on the horizon. Very cool!

Keep in mind that you don’t have to look directly toward the radiant to see the meteors of any shower. They can occur anywhere in the sky. In fact, you’ll probably see more meteors by looking away from the radiant. When you look directly toward the radiant, some of the meteors will come at you head on and won’t produce long streaks of light.

Basic meteor photography is pretty simple. Point the lens at a section of the sky where you think (hope) a meteor will occur, lock down the shutter to shoot continuous exposures, and 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 some 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.

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. Here’s more information than you want to know about shooting star trails.

While meteors streaking through star trails look good, I typically prefer to photograph them 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.

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

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 DOF 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 as complementing elements. For the Geminids, the constellation Orion, just the right of Gemini, is always a strong compositional element.

Once you set up the composition, the exposure for a pinpoint 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 speed 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, or a little shorter, 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.

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 or planets, you’ll have to recompose periodically throughout the night.

So the idea with both star trails and pinpoint stars is that you get everything set up and then let the camera do the work for a while. You want that camera making exposures for as much of the night as possible, so try to work quickly when you recompose or change batteries or something. There’s nothing worse than witnessing the most spectacular meteor of the night while you’re switching out memory cards!

Regardless of the method you choose for shooting meteors, your camera is going be exposed to the night air for a long time and you need to be aware of the possibility of dew forming on the lens. Read this article for detailed info on preventing dew.

Okay, Night Owls, get out there and catch a falling star!

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