Image Stabilization

Steady photos with this high-tech lens setting

An Image Stabilizer (IS) lens helps combat the effects of camera shake.

The technology can only compensate for small movements of the camera and lens, rather than jelly-scale wobbles, and it has no effect on moving objects in the picture; if the shutter speed is too slow to freeze them, you’ll still end up with a soft image.

Not all IS lenses are equal in terms of their shake-stopping power, but four ‘stops’ of stabilization is routine. This means, in theory, the lens can be handheld at shutter speeds that are four stops slower than suggested. So, 1/400 sec is the minimum recommended shutter speed for sharp handheld photos with a 400mm lens, but that can drop to 1/25 sec with a four-stop stabilizer on board.

Before you can activate the stabilizer in a Canon EF and EF-S IS lens, it needs to be switched on via a switch on the lens barrel. Some lenses have an extra switch that lets you to change the IS mode. Mode 1 is the standard setting, designed to correct for both horizontal and vertical vibrations. Mode 2 is for when you pan the camera to follow a moving subject.

Here, the IS system won’t compensate for the panning, and will instead correct for movement in the opposite plane (so up/down if you’re moving from side to side). Some of the high-end lenses have a third mode, which activates the IS when the shot is actually taken.

Canon’s EF-M IS lenses, which are compatible with the EOS M range of compact system cameras, have the stabilizer activated by default. You can turn it off in the camera’s menu, do this when using a tripod.