For a number of years, Canon’s solution for helping to overcome the effects of camera shake – where unintentional movement of the camera during the exposure results in blurry images – was by way of image stabilisation in its lenses. The inclusion of IS has increased over the years, and in mid-2020 Canon took this one step further by developing in-body image stabilisation (IBIS) to complement its optical designs.
Here we look at how the optical IS works, and when it is effective for your photography.
How it works
Canon's Image Stabilisation (IS) is controlled by a group of elements inside the lens which moves at right-angles to the lens axis. The movement of this special lens group is controlled by an on-board microcomputer and it works by counteracting the shaking of the camera.
When IS is switched on and the shutter button is partially depressed, the stabiliser lens group, which is locked in a central position when not active, is released. Then two gyro sensors start up and detect the speed and angle of any camera movement. The detection data is passed to a microcomputer which analyses it and prepares an instruction for the special stabiliser lens group. This instruction is transmitted to the stabiliser lens group which moves at an appropriate speed and angle to counteract the camera movement.
This complete sequence is repeated continuously so that there is an instant reaction to any change in the amount or direction of the camera shake. It takes about one second from the moment you partially depress the shutter button for the stabilisation to become really effective. The stabilisation action continues for about a second after you take your finger off the shutter release.
