“Why does exposure not automatically lock when I use Spot metering, but it does with Evaluative metering?”
Alvin Watson, Chelmsford
BRIAN SAYS… For many years, an automatic exposure lock was applied while using One-Shot AF and Evaluative metering. Any other metering patterns exposures do not automatically lock: it is necessary to use the AE-Lock button. When the EOS 6D was introduced, a new custom function was added that can enable the automatic lock with any of the metering patterns. Check your camera custom functions for ‘AE lock metering mode after focus’.
It’s important to remember that Spot or Partial metering is only measured at the centre of the frame: it is not linked to the AF point position. With AI Servo