Canon: Cancelling the AE Lock

There are two ways of locking the exposure settings:
Do nothing, it's already done for you if:
- You are using Evaluative and
- You are using One-Shot AF
Whenever you are pressing the shutter half-way in evaluation and one-shot modes, all Canon dSLRs (to date) do an AE Lock. You can see it in action by moving the camera around and you will see that the exposure settings will not change.
- Press on the AE Lock button, the <*> on the back camera and it will light the <*> in the viewfinder and lock all the exposure settings.
The AE Lock works for 4 seconds. It needs to be done again to lock the exposure settings for another 4 seconds.
The next question is how to cancel the AE Lock? There are three alternatives:
- Point the camera somewhere else and press the AE Lock again. This will replace the existing exposure settings lock with the new data.
- Wait for 6 seconds to completely clear the AE Lock.
- Press on the AF point select button which is at the right of the AE Lock <*>. The AE Lock will be released immediately without getting a new reading.
