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 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 an EOS M mirrorless camera or motorsports with an EOS DSLR.
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 Canon EOS M6 Mark II and Canon EOS 90D. Your camera will automatically adjust the aperture to produce a standard exposure. The top shutter speed on an EOS camera is either 1/4000 sec or 1/8000 sec, and the longest automatically-set shutter speed is 30 seconds.
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 whether you are using a lens with a built-in IS (Image Stabilizer) and how windy it is. 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 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!