HOW TO USE AUTO EXPOSURE LOCK

Auto Exposure Lock or AE Lock is a useful feature for those learning about their cameras and working in the semi-automatic modes on the camera (Program, Aperture Priority and Shutter Priority). Because it can’t be used in full Manual mode, it’s often overlooked but it is a useful tool to understand.

- Jo Plumridge

WHAT IS AUTO EXPOSURE LOCK AND WHY WOULD YOU USE IT?
On the back of your camera you’ll find a button labelled AE-L. This is your auto exposure lock button. Hold this button down and you’ll lock the exposure. If you then move the camera to recompose your shot the exposure settings won’t change, as long as you keep holding down the AE-L button.

The AE-L button is useful if your subject isn’t centred in an image and you want to make sure that subject is exposed correctly over the rest of the shot. It’s also useful if you want to achieve a consistent exposure over a number of shots (you might be stitching together a panorama for example). It can also be used to lock in the exposure of a blue sky, to prevent it from overexposing when you recompose to include a foreground.

HOW TO USE AUTO EXPOSURE LOCK
Firstly, you need to position your focal point over the part of your image you want to lock exposure on. Meter off this point to get your exposure reading and then push and hold down the AE-L button. Now you can recompose as required and take the shot. You can continue taking photos at this exposure as long as you keep holding down the AE-L button, meaning you can move the camera around or move your subject around without altering any settings.