How to master shutter speed

Changing your camera's shutter speed is one way to adjust the overall exposure of an image. But it also has creative uses, allowing you to control the amount of motion blur (or lack of it) in your images.

Here are five tips to help you get to grips with shutter speed and take more control over your action photography, whether you're shooting a school sports day with a Canon EOS R100 (which has a shutter speed of up to 1/4000 sec) or wildlife with a Canon EOS R7 (which offers a fast shutter speed of up to 1/16,000 sec).

Shutter speed is the length of time your camera's shutter stays open, and therefore how long the sensor is exposed to light. The longer it's open, the more light hits the sensor and the brighter the image.

Shutter speed is one side of the exposure triangle – the three factors that determine the exposure of an image. The other two are the aperture and the ISO setting. The aperture is how wide or narrow the lens opening is, which also affects how much light reaches the sensor. The ISO setting controls the sensor's sensitivity to light – a higher ISO results in brighter images, but usually at the cost of increased image noise.

A fast shutter speed such as 1/1000 sec, which means the shutter stays open for just a millisecond, can freeze the motion of a fast-moving subject, such as a motorcyclist travelling at speed. A fast shutter speed, however, means less light enters the camera, so you'll normally widen the aperture or raise the ISO to ensure a well-exposed image. A very slow shutter speed such as 1 second would result in the moving motorcyclist being blurred.

The majority of EOS cameras have a 'Sports' Special Scene Mode that will automatically set up the camera's exposure and focusing settings for shooting moving subjects. This will give you great results, but you can take more control when you want to get creative, produce a particular effect or adjust for the specific circumstances, such as when you're shooting a fast-moving subject handheld from a distance.

To take direct control of the shutter speed, set your camera to Shutter Priority (or Tv, which stands for Time Value). You can then set the shutter speed by rotating the camera's main dial, or by using the touchscreen that's available on many EOS cameras, including the EOS R50 and EOS R8. Your camera will automatically adjust the aperture to produce a standard exposure. If you want to take full control, switch to Manual mode (M) and you can choose any combination of settings you like.

The fastest shutter speed available varies between models, and also according to which shutter mode you select, where a choice is available – mechanical shutter or electronic shutter. The mechanical shutter on a Canon EOS camera typically goes up to either 1/4000 sec or 1/8000 sec, while the electronic shutter in advanced mirrorless EOS R System models can be much faster – up to 1/64,000 sec in the EOS R3. The longest automatically-set shutter speed is 30 seconds. If you want longer exposures, for example for capturing fireworks or light trail photography, you can select Bulb mode. In this mode, the shutter opens when you press the shutter button and stays open until you press it again.

There are two things to think about when you're choosing the shutter speed: whether it is fast enough to avoid blur due to camera movement when you're shooting handheld – also known as "camera shake" – and how quickly the subject is moving.

The shutter speed you need to avoid camera shake depends on a number of things, including how windy it is and whether you are using a lens or camera with built-in image stabilisation. But the focal length of the lens is the most important factor. The more you zoom in, the more noticeable any shake becomes.

A general rule to eliminate this problem is to try to use a shutter speed that's equivalent to the inverse of the effective focal length or faster. So with a 50mm lens setting, use 1/50 sec or faster, and with a 200mm lens use 1/200 sec or faster. Then you need to factor in the speed of the subject – read on.

The shutter speed required to freeze a moving subject depends on the distance it is from the camera, the direction it's moving and its speed, but you'll probably need a shutter speed faster than you might think. A shutter speed of 1/250 sec will freeze a slow-moving subject, such as a person walking, but you'll have to go as high as 1/1000 or even 1/4000 sec for sharp shots of faster subjects such as flying birds and speeding cars. Be prepared to increase the ISO setting to keep the exposure correct when you use faster shutter speeds, especially when you're photographing sports and wildlife.

The downside of freezing the action can be that it doesn't look like action any more. Pictures of moving subjects often look more dynamic if the subject is sharp but the background is blurred. To achieve this effect, make sure the shutter speed is slow enough to give you some blur, then move the camera with the subject, at the same speed as it's moving. This is called panning – learn more in our handy guide to panning.

When you're capturing video, a useful rule of thumb is to set a shutter speed of around 1/2R, where R is the frame rate you're shooting at. For example, if you shoot at 4K 60p on the Canon EOS R10, the ideal shutter speed is about 1/125 sec – just over double the 60fps the camera is shooting at. This avoids blur from too slow a shutter speed, but prevents footage looking choppy, as it would if you used faster shutter speeds.

You can use a relatively long exposure – a slow shutter speed, longer than a second, say – to intentionally blur a picture or blur just the moving elements within an otherwise sharp scene. To prevent this overexposing the shot, though, you'll need to use a narrower aperture setting (higher f-number, such as f/16 or f/22), a lower ISO setting, or an ND filter to limit the amount of light entering the camera. Now you can either move the camera during the exposure (which will blur the whole photo) or use a tripod to keep the camera stationary so that only the moving parts of a scene are blurred. Try the latter technique to soften waves and flowing water in a landscape, or to blur moving vehicles and crowds of people in a city scene.

For exposures longer than 30 seconds, use Bulb mode. Some Canon cameras have a 'B' setting on their mode dial, while others need to be set to 'M' (Manual) before you can scroll through the shutter speeds until 'BULB' is displayed. A remote timer or wired remote can be useful, to eliminate the risk of jarring caused by pressing the shutter button. You could also consider using the Canon Camera Connect app to control your camera remotely from your smartphone.

Understanding shutter speed, and how to control it, will enable you to get the most from your camera and lens, helping you capture great images every time.


Written by Marcus Hawkins and Pete Wolinski