There are three settings on your camera that affect how bright a photo turns out. Shutter Speed, Aperture and ISO.
Shutter Speed is the easiest to understand, which is why it is first in our series of beginner articles.
What Is Shutter Speed?
Shutter Speed is the length of time that the shutter of your camera is open when you take a photo. It is the amount of time that the sensor at the back of your lens spends collecting light to create the photo.
The longer your shutter is open, the more light is collected by the camera sensor, and the brighter your exposure will be.
Shutter speed is generally measured in seconds. Most cameras have a fastest shutter speed of 1/8000 or 1/4000 of a second (although some are even faster) and can slow down to around 30 seconds or longer.
Most DSLRs will also have a 'bulb' mode that will allow the shutter to be open for as long as your battery will allow, but you will need a remote to 'hold' the shutter open for that long (you can't just set it via the camera's dials).
Pretty simple. Let's dig deeper.
How Shutter Speed Affects Photos
Changing the shutter speed on a photo has two main effects. It will change the brightness (exposure) of your photo and it will control motion blur:
Longer shutter speeds allow for more light to be captured by the sensor. Every time you double the length of time the shutter is open, you double the brightness of the photo (ISO and Aperture are kept the same).
Below you can see the effect of changing the shutter speed on the brightness of a photo.
Shutter Speed and Motion Blur
Another important side effect of shutter speed is the amount of motion you capture in your photo. If you're taking a photo of a moving subject, let's say a bird in flight, with a slow shutter speed it will probably be blurry.
Let's explore why!
When you choose a fast shutter speed, say 1/2000th of a second, the bird won't move very far during that time.
When you choose a slow shutter speed, say 1/10th of a second, the bird will move a lot more during that time. The movement will show up as blur in the photo.
Shutter Speed and Camera Vibration
There is a second form of motion blur, caused not by movement of the subject, but movement of the camera and/or lens.
A tripod will help to eliminate camera vibration and movement during a capture
When hand holding, a camera and/or lens optical stabilisation system (known by VR, IS, OS, IBIS.....etc) will help to reduce camera and lens movement.
In addition to the above two options - higher shutter speeds will also help to reduce any camera movement. See the 1/Focal Length 'Rule' below:
Choosing A Shutter Speed
Unfortunately there is no set formula for choosing a shutter speed.
Assuming you are looking for sharp photos with no motion blur, there are a few general guidelines that you can follow.
There are however, some general guidelines you can follow.
The 1/Focal Length 'Rule' to Stop Camera Motion
The word 'rule' is in quotes because there are no such things as set rules in photography. It is a guideline and should be adjusted as each photo requires.
When hand-holding your camera (ie, not using a tripod) the 'rule' state that you should use a shutter speed at least 1/[Lens Focal Length].
- For a 50mm lens your minimum shutter speed should be 1/50 sec
- For a 200mm lens your minimum shutter speed should be 1/200 sec
- For a 600mm lens your minimum shutter speed should be 1/600 sec
The above guideline accounts only for camera movement, and does not take into account if your subject is moving. As mentioned above, tripods and vibration reduction systems will mean you can lower the speeds required to keep things sharp.
Action Photography Shutter Speeds
In this case, 'action' photography indicates any form of photography where your subject is moving and you don't want any motion blur.
A very rough guide to shutter speeds to stop movement:
- A person walking: 1/200th
- A person running: 1/500th - 1/1000th
- An animal running : 1/800th - 1/2000th
- A bird in flight: 1/1500th to 1/3200th
Just remember that the faster your subject is moving in relation to your camera, the faster your shutter will need to be to 'freeze' the action.
Still Life Shutter Speeds
If your subject isn't moving then you can generally get away with much longer shutter speeds. If you are using a steady tripod then there is no real limit to what you can choose (depending on how much light there is in the scene).
If you're hand holding your photo then you can use the 1/Focal Length Guideline as a starting point to eliminate any blur from camera movement.
Flash Shutter Speeds
When using a flash, you will usually be limited by your camera's flash-sync speed. This will probably be somewhere between 1/200 and 1/250th of a second. You won't be able to choose faster speeds than that.
The good news is that if the flash is the main source of light in the photo, it will help stop any motion in the photo. The flash provides a very quick burst of light and is like using a higher shutter speed.
Using 1/60 - 1/200th of a second will be OK for general flash photography.
How To Set Shutter Speeds
Every camera is different and we can't go through them all.
To choose a shutter speed you will need to set your camera to 'Shutter Priority' mode. In this mode you will dial in the shutter speed that you want and the camera will pick an appropriate aperture (and ISO if you have enabled auto-iso).
Once in Shutter Speed mode you will be able to dial in a shutter speed appropriate for the scene you are currently photographing.
If you need a shutter speed longer than your camera can do in Shutter Speed mode (typically 30 seconds) you will need to set the camera to 'Bulb' mode (indicated by the 'B' on the dial in the above photo). You will then need to attach a remote shutter release so you can manually control how long the shutter is open for.
Your shutter speed determines how long the camera spends collecting light when taking a photo. A longer shutter speed will result in a brighter photo.
Shutter speed also allows you to control the amount of motion blur in your photos. Longer lenses will require faster shutter speeds if the camera isn't on a tripod. The same applies if your subject is moving. More movement requires faster speeds to freeze the action.
To control the shutter speed on your camera, change it to Shutter Priority mode and then dial in the desired speed.