EOS AF points

When shooting with an EOS SLR camera, you should remember that the AF point that you see in the viewfinder doesn’t exactly correspond with the AF sensor inside the camera. In fact, the AF sensor inside the camera is larger than the AF point you see. This means that it is possible for the camera to focus on an area slightly outside of the AF point as you see it. To counteract this, always keep an eye on the areas around your chosen AF point as well – if there is an area of better contrast to the side, you may find the AF point locks onto that instead.