How to photograph a meteor shower

A major meteor shower, such as the Perseids in August or the Geminids in December, is a treat for anyone with a bit of patience to sit out and watch. But if you have a reasonably good camera with the ability to take time exposures, you could try to photograph some too as a lasting record. Here is how to photograph a meteor shower.

A bright Perseid beneath the Andromeda galaxy (M31). Perseus itself is to the left of the frame. This was taken with the FujiFilm X-M1 and Samyang 12mm lens. Image credit: Paul Sutherland

This really rules out using cheaper snapshot cameras. Meteors appear randomly and in any direction, and they are too sudden and swift for you to be able to spot one and then take its photo. Cameras built into today’s smartphones are also not ideal, though there are apps that will stretch their capabilities and capture meteors for you, such as NightCap for the iPhone and iPad, or Camera FV-5 Lite for Android.

It remains true that it is much better to use a traditional camera, with manual settings. You then need to aim the camera and open its shutter for a while in the hope that you’re lucky and a bright meteor appears right where you are pointing. Your camera must allow you to open its shutter for at least several seconds.

You must also be able to focus the lens manually, as starlight is usually too faint for the autofocus to work, and your camera will spend all its time searching for focus and running down the battery. There is usually a switch on the lens of a DSLR camera to select manual focus.

The Canon EOS 600D with Sigma 10-20mm lens attached, on a tripod with a cable release. Image credit: Paul Sutherland

See my photos of Perseids from 2016

In the days of film, where every precious frame counted, amateur astronomers got used to seeing bright meteors appear just after they had ended an exposure, or just outside the patch of sky being photographed. Today’s digital cameras mean that amateur astronomers can rattle off hundreds of shots in succession without worrying about the cost. The chips that replaced film are much more sensitive too, meaning that fainter meteors may be imaged than before.

I have had a fair amount of success photographing meteors with a Canon digital camera, in my case the consumer model the EOS 600D. It is ideal because you can set it to take continuous exposures, providing you have a cable release, so that you don’t have to keep pressing the shutter yourself. This way, you don’t even need to stay with the camera.

I used mine to photograph the Quadrantid meteor shower on a chilly night in early January, 2016 and was able to go back to bed for an hour or two at a time, popping back to change the battery and check all was OK. (The camera was pointing out over the sea from a sheltered balcony, so I did not need to worry about the possibility of rain!)

The first important rule in taking time exposures of the sky is that you need to hold the camera steady. A photographic tripod, or similar, is therefore essential, and you should have a threaded hole in the base of your camera into which the head of this – often a detachable plate – can screw. This should be set up in a dark location, away from any street lights or other light pollution, so it is best to practise mounting and operating the camera beforehand when you can see what you are doing more easily.

The screen on the Canon EOS 600D where you select the shooting mode. Image credit: Paul Sutherland

Next, you need to set the speed of the camera – the ISO – in the camera’s manual settings. With a clear dark sky, you should set this to at least 800. Excellent conditions and an absence of interfering moonlight might allow you to go to 1600 or even higher. Experiment and see what you get when you review the first test shots.

You will next need to ensure the camera lens is in focus. Modern cameras have “live view” settings to make this easier because you cannot always rely on turning the lens, in its manual mode, to the little squiggle that marks “infinity”. Instead, select live view, then zoom in until you can see a bright star, and turn the lens until that star becomes a sharp point of light.

Make sure the lens is fully open when you focus – turn the part of the lens barrel that controls the iris of the lens so that it is set to its highest f number. To catch more meteors, you will want to have the lens wide open (at a high f number) in any case, though “stopping down” by a stop can improve the picture if the lens is not of high quality.

My Fujifilm X-M1 1with its fast 12mm f2 Samyang prime lens fitted. Image credit: Paul Sutherland

It is important here to use a solidly built lens if you can. I found, to my cost, that the light zoom lenses sold as standard with consumer DSLRs are OK for daytime shots in autofocus, but are so flimsy that they easily slip out of focus in manual mode. (I took my Canon to Iceland a couple of years ago to photograph the aurora, travelling light with just cabin baggage, and so relied on my kit lens. It was only after a fine auroral display that I saw that my stars were no longer pin-sharp.)

I now have a much more robust 10-20mm Sigma lens on my Canon with a focus that stays just where you turn it. It is a lovely wide-angle lens that covers a large area of sky, increasing the chances of catching a meteor, and I am very happy with it. Even so, it is wise to check regularly that it is still in focus (and, on humid nights, that the lens is not misting over with condensation). The downside of the lens is that it only goes up to an f number of 3.5.

As an alternative, and I must take more comparison shots, I have an excellent Samyang 12mm prime lens on my Fuji X-M1 camera – it is a robust design with good quality optics, and is also sold in the USA under the Rokinon brand.

One benefit of the Canon EOS and the FujiFilm ranges (as well as other brands, no doubt) is that you can employ lenses from various old SLR film cameras by adding an inexpensive adapter. I have several Olympus Zuiko lenses made for their OM cameras. These were beautifully made pieces of glass and the wide-angle lenses would be useful for meteor work if you already have them.

The Canon camera’s cable release. Image credit: Paul Sutherland

Finally, it helps to have that cable release if you want to take shots continuously. My Canon release, pictured, is inexpensive. I simply set my camera’s drive mode to continuous, using the leftmost of the central ring of four buttons on the back of the camera, then push and slide forward the release button to lock it. Pressing and sliding back the release button ends the run of exposures.

Even an exposure of 20 seconds, using a wide-angle lens, will reveal that the Earth is turning by recording the stars as short trails. If you want them to look more like points of light, then could mount your camera on an equatorial telescope mount with a motor drive, or one of the dedicated driven camera mounts such as the AstroTrac. Otherwise, keep the exposures to just 10 or 15 seconds long.

When I tried this set-up for the January Quadrantids, I was surprised how many meteors I had captured. The fact I left the set-up to work unattended meant that I had to scan through hundreds of images on my computer to spot the meteors. I was still finding some of the fainter meteors a few days later! However, while doing so, it is important to look out for imposters – streaks of light that are not meteors but which are caused by aircraft trails or orbiting satellites.

These two trails are more obviously produced by aircraft in this 20-second exposure, because the individual lights on their wings can be discerned. Image credit: Paul Sutherland

How to recognise false ‘meteors’

If you are sitting out watching a meteor shower, it is easy to tell the genuine “shooting stars” from other bright objects that move across the starry background. A meteor moves swiftly in an instant. An aircraft or satellite travels a much slower path and will be visible for longer.

Aircraft will leave trails due to their red, green and white navigation lights, and other beacons which may be flashing. These can make their cause readily recognisable if the aircraft is not flying too high.

This bright “meteor” is actually an aircraft. It was visible across several frames, and in this one you can actually see a slight kink as it changes course. Image credit: Paul Sutherland

But if you are taking several consecutive frames, it will also be clear that the object is not a meteor due to the trails continuing over more than one image as the aircraft continues its flight.

A high-flying aircraft might be harder to discern from its lights, but the continuing of its trail across multiple exposures will again be a giveaway. Often you will also see it kink as it changes course!

The other major meteor “imposters” are satellites, and with many thousands now in orbit, it is inevitable that several will cross your camera’s field of view while you are taking your exposures. If you are checking through your images later, it can be tricky to tell some of these from meteors.

What may look like a meteor in a single frame can be seen to be a satellite trail over several exposures. Image credit: Paul Sutherland

Satellites do not carry lights, and they shine due to sunlight reflecting off them. If the satellite’s structure is uniform, then this can allow them to shine with a steady glow as they travel across the night sky.

However, an otherwise dark satellite with a particularly reflective part of its structure can brighten and fade as that part of the spacecraft catches the sunlight.

Most satellites are rotating, and the glint of sunlight can occur very briefly as a sudden flare. Iridium satellites used to be particularly famous for producing brilliant streaks which closely resembled meteors, but these have been steadily decommissioned and de-orbited.

The centre image looks like a meteor, but the previous and following frames show that it was a satellite brightening and fading. The three exposures were taken over a period of one minute. Image credit: Paul Sutherland

An iridium satellite could usually be identified by the symmetrical nature of the brightening and fading, plus the time of their flaring from a particular location could be predicted using a website such as Heavens Above.

Other satellites that gradually brighten and fade may be identified in the same way as aircraft trails. The object will be seen across images taken over more than one exposure.

It looks like a meteor at first glance, but the symmetrical pattern shows that it is a flare from a satellite catching the sunlight. Image credit: Paul Sutherland

I have taken many sequences where a satellite brightens from nowhere and then fades out of view again over three or more shots. Since each exposure of mine typically lasts 20 seconds, this shows that the object has been tracing its path for much longer than a meteor would.

It is harder to separate the satellites that flare suddenly and briefly in a single frame. But as with the iridium satellites, the symmetrical nature of the flare will usually tell them apart. It is quite unlike the uneven bright streak of a meteor such as that at the top of this article.

Related: How to observe meteors

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