The first cause is simply holding the camera incorrectly. The solution to camera shake is just as simple: hold your camera correctly. Whether you use simple digital cameras or the latest SLR digital camera, the proper hold is the same: Hold your camera close to the body. Tuck in your elbows snugly against your sides. Maintain a steady and relaxed grip on your camera. Stand with your legs roughly a shoulder’s width apart.
The aim of these suggestions is to stabilize both the camera and your body. This will ensure that camera remains as still as possible.
The second cause are simply common mistakes made during shooting that increase the likelihood of camera shake. Even if you have a top-of-the line Sony digital camera with monitors, you will still need to avoid these common mistakes to ensure your camera images are the clearest they can be. When shooting pictures make sure to avoid the two most common errors: Jabbing the shutter release button hard instead of gently pressing it. Moving the camera away from your eye right after a shot is completed instead of holding the camera at eye level for an additional moment after the shutter motion has completed
Another common mistake is using a shutter speed that is much too slow, which can make your images look blurry. Slow shutter speed is usually considered to be about 1/60th of a second or any speed that is lesser than the total focal length of the camera lens. For example, if a 300mm lens is used, then a camera shutter speed of 1/300th of a second might still be much too slow to get any sort of clear image. However, if you are instead using a 28mm camera lens, then 1/60th of a second would be considered slow. The reason slow camera shutter speeds are troublesome is because the human hand does not stay steady. Larger lenses like the 300mm will increase the weight in the hand and create camera shake. Using a higher shutter speed will decrease the amount of time of the shutter’s exposure as well as reduce the amount of camera shake that is then transferred to the picture.