Motion blur

Imagine this: you’re trying to take a photo of your friends with your camera, but the light is dim and you can’t use a flash. The camera seems to focus successfully, so you click the shutter, but the resulting photo is totally blurry.  Oh no!  Sound familiar?

What you’ve just experienced is known as motion blur.  It’s caused when either your camera or what you’re photographing moves during the exposure.

Motion blur is most often a problem when the light is dim.  Your camera compensates for the reduced light levels by taking a longer exposure.  The longer the exposure, the more time there is for movement, and if there’s movement, there’s blur.

Modern point-and-shoot cameras and DSLR lenses incorporate image stabilization systems which can eliminate some types of motion blur to a certain extent, but the best strategy is still prevention.

Here are some tips for reducing motion blur:

  • Use a faster shutter speed: The shorter the exposure (i.e., the faster the shutter speed), the less time there will be for movement.  A rule of thumb for photographing stationary objects is to use a shutter speed at least as fast as the reciprocal of the effective focal length.  For most point-and-shoot digital cameras, that means a shutter speed of at least 1/30 second at wide angle, and at least 1/150 second when zoomed all of the way in.
  • Add more light: If it’s possible to add more light to the scene, that will allow you to use a faster shutter speed.
  • Increase your camera’s sensitivity: No, this doesn’t mean you need to teach your camera to “actually listen” to you.  It means that you can try increasing the ISO sensitivity level, which is somewhat analogous to turning up the “volume” on its light sensor.  If your camera is set to 200, try 400.  If it’s set to “auto,” try a higher manual value, perhaps 800.  Be aware, however, that there’s a trade-off: the higher the sensitivity, the noisier/grainier the photos will be, which can result in blur of a different sort.
  • Remind everybody to stay still: If the problem is not that the camera is moving, but rather that the people in the photo are moving, then don’t be afraid to tell them to stay still.  Depending on your camera, they might need to remain stationary for some time before or after they hear the camera click in order to prevent blur.
  • Use a tripod or other brace: If you can hold the camera still using something like a tripod, that’s a win.  If you don’t have a tripod, any other solid object can serve a similar purpose.  Tables, fence posts, and car hoods are some often-convenient options.
  • Hold the camera tight to your body: Your body will experience less movement than will your hands.  Therefore, you can use your body as a sort of crude brace.  Grasp each side of your camera with your hands, then bring your arms in and hold them tightly against your chest.  Alternately, turn your head to the side and hold your camera on your shoulder.  You’ll be able to frame your image while enjoying a relatively solid bracing surface.

Have other ideas?  Feel free to add them in the comments!

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