Metering

[Fiendish Astronaut]

There are a few things about metering which I'm not sure about. For instance, if I have spot metering and I focus on a face in the metering circle (which marks where the spot is), then I recompose the shot whilst in focus lock, what happens to the metering? And what about if the lights change?

Hmm...

 

[Big Mike]

You can use Exposure Lock...which might be activated by holding the button halfway down. Or you could use manual mode...just meter, lock in those settings then recompose to your heart's content.

If the light changes, then you would need to re-meter and/or compensate for that.

 

[Fiendish Astronaut]

That was a quick reply - thanks Mike. This is what I would think but with my camera on AV mode I've noticed my camera's shutter speed altering when lights change even when I'm half-pressing my shutter. Must investigate this further - perhaps I'm mistaken...

 

[Big Mike]

Your camera might be set for auto focus lock with the shutter button...but not exposure lock. Check the manual, but exposure lock might be on the * button by your thumb.

Personally, I have my AF set to be triggered with the * button and the shutter release button controls the AE lock...although, I'd probably use manual mode in this scenario.

 

[Sideburns]

Mine is opposite to Mike's...
My autofocus is half shutter, and AE lock is the * button.

Try pushing the * button. It locks in your metering. So meter off their face, push the * button, then recompose and take the picture.