Motion blur is one of the best ways to add visual interest to a photograph. It is also one of the most challenging! In part 1 of our tip on motion blur (you can read it here) we discussed keeping the camera still and using the movement of the subject create the blur. In this tip I will explain the best way to get motion blur by moving the camera.
Using motion blur by moving the camera can serve four different purposes.
- Drawing the viewers attention to your subject by making everything else a blur.
- Giving a strong sense of speed and movement to your subject.
- Creating an overall sense of movement to a scene.
- Creating an abstract image.
Creating motion blur by moving the camera is achieved in the same way as having a moving subject in the image, by doing a longer exposure. The difference is that you don't tend to do as long of an exposure. The best ways to create a dynamic image are by:
- Panning the camera at the same speed as your subject (this creates a strong sense of directional movement and speed.)
- Using a strobe to freeze your subject while blurring the background (this leaves a lot more room for error since the strobe freezes the subject for you.)
- Changing the focal length of a zoom lens during a longer exposure (this is a great way to create an abstract image.)
There are a lot of variables to take into consideration to create the amount of motion blur you want. Things to consider are:
- The amount of light available
- The length of your exposure
- The visual distance from your subject
- The speed of your subject
With all the possible ingredients in a motion blur shot, the recipe changes from shot to shot dependent on what you are trying to achieve and the different variables involved. Let's go over each piece and talk about how it effects your final image
The amount of light available is key and it's influence on your exposure. No matter how much blur you are trying to achieve, you still want a proper exposure. The best thing to do is expose for your overall scene and then adjust your aperature (making the opening smaller) so that you need a longer shutter speed to get a proper exposure. This can range anywhere from 1/250th of a second to seconds depending on what you are trying to achieve. The longer the exposure the more blur you will create and the more abstract your background becomes.
The visual distance from your subject is dependent on your location in relation to the subject and the length of lens you are using. If you are using a 300mm lens to zoom in on you subject, it takes less movement to create blur. Sometimes when you are zoomed in on a person walking, you can create a good amount of blur by having your shutter speed set to 1/60th of a second. If you are shooting at a wider focal length (let's say 50mm) with the subject the same distance from the camera, it takes much more movement of your camera to create the blur.
The last element to pay attention to is the speed of your subject. A race car and a walking toddler move at much different speeds. The faster the subject is moving the shorter you want your shutter length to be. The longer you leave the shutter open, the more potential error you have in panning with your subject.
Capturing motion blur shots by moving the camera is really something that takes a lot of trial and error to get right. So get out there and shoot!

Using a flash to "freeze" your subject while creating motion blur in the background.

Panning with the subject to create a strong sense of movement.

Zooming with the lens during a longer exposure to create an abstract image.