Astrophotography: night sky and star photography tips

Standing outdoors at night and gazing up at the stars is a truly magical experience. Nowadays, thanks to advances in camera technology, it's easier than ever to get out there and capture the wonder of the night sky.

Here, we explore how astrophotography works, the equipment needed for night photography, including time-lapse and star-trail images, and the best night photography techniques and camera settings.

Before you go out to shoot, don't forget to check the forecast, as you'll need a clear night sky to achieve the cleanest star photography. That said, partial cloud cover can actually add atmosphere to your night sky pictures, so be creative and use the weather to your advantage. Keep an eye on the wind: if the clouds are relatively still, they won't look too blurry in shots where you're using a long exposure.

Pack spare batteries and memory cards, a head torch and warm clothing. Remember to keep batteries in your pockets as they drain more quickly when exposed to the cold.

To get the best night sky pictures, you'll need to head out into nature and away from any light pollution. A range of online resources, such as light pollution maps and the Bortle scale, can be used to identify areas that will be suitable for photography. Look for a quiet spot with no artificial lighting. City lights will overpower stars, but so will a full or even a half moon, so check your lunar calendar when planning your star photography shoot.

The best time to photograph the Milky Way in the northern hemisphere is between March and September, when it appears highest in the sky. Aim to shoot between midnight and 5am, ideally on nights with a new moon. The Milky Way season lasts longer in the southern hemisphere, from February to late October. Check websites and apps for the exact times of astronomical events, so you can plan where to stand and when to shoot.

To shoot starry skies, you'll need to take control of your camera, so select Manual (M) mode and try out some of the different settings detailed below:

• Shutter speed: Stars move as the Earth spins, so if you want to capture precise pinpricks of light, set your shutter speed to between 6 and 20 seconds. Extending it beyond this will result in star trails.
• Aperture: You'll also need to use a wider aperture setting (ideally anything from f/1.4 to f/2.8, but f/4 is fine if you do not have access to a fast lens). This will allow you to let as much light as possible into the camera while keeping the exposure time relatively short. Remember that a wide aperture will result in a shallow depth of field, meaning anything in the immediate foreground will be out of focus.
• ISO: The third factor affecting the exposure of your photos is your ISO setting. The higher your ISO number, the more sensitive your sensor will be to the light entering through the aperture. Go too far, though, and your images will start to look grainy. Make sure you're happy with your aperture and shutter speed before experimenting with your ISO settings. Try an ISO of 1600 at first and adjust from there to see how this affects your results.

Night sky photography can challenge the autofocus capabilities of any camera. Consider switching to manual focusing by flipping the AF/MF switch on the barrel of your Canon lens. If your lens doesn’t have this switch, select MF in the camera menu instead. Mirrorless cameras such as the Canon EOS R6 Mark III and EOS R8 offer a magnified preview of the scene both in the electronic viewfinder and on the rear screen, enabling ultra-precise manual focusing. Another bonus is that the brightness of the viewfinder image is automatically boosted.

Cameras that boast high megapixel counts, such as the Canon EOS R5 Mark II, can have a huge impact on night sky photography, enabling you to retain ultra-fine detail when photographing the stars. It can mean the difference between the smallest, faintest stars being clearly visible, or missing altogether. This level of detail is especially important if you want to produce prints of your starry night sky images*.

Lenses with a 'fast' aperture rating are always preferable for star photography, and they don't need to cost a fortune. The Canon RF 35mm F1.8 Macro IS STM makes a superb astrophotography lens, for example. The moderately wide field of view of this lens takes in a large swathe of the night sky, while the fast aperture pulls in lots of light, and optical image stabilisation enables handheld night shots. For capturing even more expansive shots of the Milky Way, the Canon RF 16mm F2.8 STM, Canon RF 24mm F1.8 MACRO IS STM or super-slim Canon RF 28mm F2.8 STM are ideal, combining a wide field of view and fast aperture with a compact build.

If you prefer the flexibility of a zoom lens, the Canon RF 24-105mm F4-7.1 IS STM stretches from a generously wide field of view to a telephoto focal length, meaning this lens can double as a portrait and wildlife lens. It also features image stabilisation, allowing you to slow your shutter while shooting handheld. For photographers wanting even higher quality at this focal range, the Canon RF 24-105mm F4L IS USM offers professional-grade L-Series optics and full weather sealing.

The Canon RF 28-70mm F2L USM is a spectacular standard zoom for astrophotography, with an incredibly fast f/2 maximum aperture. For extra width at the wider end, where a few millimetres go a long way, try the Canon RF 24-70mm F2.8L IS USM.

The Canon RF 15-35mm F2.8L IS USM, an ultra-wide-angle zoom, enables you to capture vast amounts of the night sky, while still enjoying a fast aperture rating and flexible zoom range. The more portable Canon RF 10-20mm F4L IS STM and Canon RF 14-35mm F4L IS USM are good alternatives – each only an f/stop slower and providing an even greater maximum field of view – while the Canon RF 16-28mm F2.8 IS STM is another bright, lightweight option.

Arguably the best Canon lens for astrophotography, the Canon RF 14MM F1.4L VCM combines a sweeping view with a very fast aperture, making it easier to freeze the movement of stars. Like the other bright, wide-angle RF hybrid lenses, it uses Canon’s advanced optical technologies to help produce beautiful, crisp night-sky photos, and it’s surprisingly lightweight for such an impressive lens. Find out more about why RF lenses can give you the edge when shooting at night in our guide to the best Canon kit for low-light photography*.

If you're looking for a lightweight, affordable zoom for an APS-C mirrorless camera, such as the Canon EOS R100 or EOS R50, the Canon RF-S 10-18mm f/4.5-6.3 IS STM offers an ultra-wide view that works well for dramatic night sky shots, while weighing only 150g.

Elevate your night sky photography by including other elements to bring more visual interest – buildings, trees, mountains, or reflective lakes are all good options. Sometimes stars photographed on their own can result in images that lack perspective or personality, so always look for something unique that you can shoot to add to your image.

A traditional technique for retaining sharpness in a scene from the foreground to the background is to set the lens to its hyperfocal distance. There are numerous smartphone apps available which can calculate this distance for you. Many modern lenses don’t have a focus distance scale, but most Canon EOS R System cameras are able to display focus distance in the viewfinder when using RF lenses.

Checking different areas on the camera's rear screen with a magnified preview enables accurate manual focusing but, given the shallow depth of field at wide apertures, it can be impossible to get the whole scene in focus. An alternative is to take two or more shots at different focus and exposure settings, separately tailored to foreground areas and the distant starry sky, and then to merge them into a single image with an editing program that features layer masks, such as Adobe Photoshop¹.

If you'd rather capture everything in a single shot, but foreground areas are very dark, try illuminating them with a flashgun such as the Canon Speedlite EL-10, firing one or more pulses of light during a long exposure. You can also get creative by sweeping light over specific foreground objects and areas of interest during a long exposure with a torch, or even the headlights of your car if you've driven to a shooting location.

Capturing fantastic lines of light showing the movement of the stars is a challenge, but mastering the technique is possible by following a few simple steps. Start by locating the North Pole, which is easily achieved using a star chart app on your smartphone. Positioning yourself so that the North Pole (or the South Pole if you're in the southern hemisphere) is the focal point of your photo and using a long exposure will result in the circular pattern forming around a central location. Remember, for any long exposure shot, it's important to use a tripod to avoid motion blur.

Stars don't give off much light, so use a high ISO (800, 1600 or higher) to produce clear star trails. Take a few experimental snaps before attempting a long exposure, as the higher the ISO, the more likely you are to encounter 'noise' in your image.

Although it takes 24 hours for the stars to complete a full revolution in the sky, the appearance of a full-circle star-trail effect can be achieved with a long exposure of around 60 to 90 minutes. If you're shooting in the northern hemisphere, locating the Polaris star in the night sky will give you a reference point around which the stars will appear to rotate.

The slowest shutter speed available on many cameras is 30 seconds, so you'll need to use the Bulb exposure setting in Manual (M) mode. This allows you to keep the shutter open for as long as you want to. Set your focus to infinity, and once you're ready, try an exposure of around 30 minutes. Then review your shot again. It may take a few tries – and some patience – but eventually you'll achieve results you're happy with.

Another option is to create a night sky time-lapse video. You can do this manually by shooting a sequence of still photos and compiling them into a video later, but many Canon cameras – including the Canon EOS R6 Mark III, EOS R8 and EOS R50 – feature a Time-lapse movie shooting mode. This utilises a built-in intervalometer to automatically capture images and combine them into a single video file that’s ready to share.

Mount your camera on a tripod and switch to Manual exposure in video mode. Set a shutter speed of around 20 seconds or less, then adjust your aperture and ISO to achieve a good exposure (f/4 and ISO 640 often work well as a starting point). Take a test shot and review the results, making any necessary changes to your exposure settings.

Next, select Time-lapse movie shooting in the menu and set the intervalometer to take successive shots every couple of minutes or so. The total shooting time for the sequence will depend on how long you want your night sky time-lapse video to be, as well as the frame rate you choose. For example, a sequence of 60 shots at a frame rate of 30fps will produce a two-second time-lapse video.

A well-made star time-lapse can be astounding, with the heavens appearing to gradually spin before your eyes. If you're lucky, or plan your shoot to line up with a meteor shower, shooting stars will dart across your frame, adding to the galactic wonder. Find out how the pros capture this stunning celestial display in our guide to photographing meteor showers*.


Written by Matthew Richards and Marcus Hawkins


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1. Adobe and Photoshop are either registered trademarks or trademarks of Adobe in the United States and/or other countries.</sup>