Shooting for the Stars: A Beginner’s Guide to Photographing a Comet

A new comet, named C/2022 E3 (ZTF), will be making a close approach to Earth in the coming weeks. On February 1, it will pass within 28 million miles of Earth, which is its closest approach in 50,000 years.  In fact, the last time the comet visited, the Neanderthals still walked the Earth!

If you are lucky enough to be able to see the comet, you could be wondering how to photograph it.  Here are some tips to get you started.

1.      Use a long exposure: Comets are relatively faint objects, so you’ll need to use a longer exposure to capture enough light to create a visible image, but your shutter can’t be open too long or you’ll risk blurring the tail. You’ll want to use a shutter speed of at least 30 seconds, but longer exposures of several minutes may be necessary to bring out the details of the comet’s detail.  Start around 1-5 seconds.

2.      Use a wide aperture: To capture as much light as possible, you should use a wide aperture (low f-stop number) to allow more light to reach the sensor. So set your aperture as wide as your lens allows.

3.      Up your ISO: when photographing a comet, ISO setting depends on the time of night, the level of light pollution and the brightness of the comet itself. If the comet is being shot closer to sunrise, the ISO can be lower, but when shooting in the twilight hour, the ISO can be raised to around 1000-2500 to capture more of the comet tail. If the comet were visible during complete darkness, the ISO should be closer to 2000.

4.      Use a tripod: Long exposures will create blurry images if your camera is not steady. So you must use a tripod to keep your camera steady and avoid any camera shake.

5.      Use a remote or cable release: To further reduce camera shake, use a remote or cable release to trigger the shutter instead of your finger to press the button. The cameras self-timer also works if you don’t have a remote shutter release.

6.      Focus: Focusing on a comet can be tricky, but you can use the stars in the background to set your focus. Switch your lens to manual focus and focus on the brightest star you can find in the image, this should give you a good focus and then you can recompose your image as needed.

7.      Experiment: The above tips should get you started, but don’t be afraid to experiment with different settings and techniques to see what works best for you.

Also note that the weather conditions and location are important, and you will need clear night skies with as little light pollution as possible. And be patient, comets can be faint objects, but usually are worth the wait!