Meter Operating Time

What does this mean? What is it for?

It is the length of time the meter circuit stays activated once the shutter release has been half pressed to switch it on.

I always wonder what the advantage to a short operating time is. Does the meter consume a lot of battery power?

It's not really significant, not in a K20D that does 700 shots on one charge anyway.

I use 10 seconds, but it could happily be longer. Shorter might be a bit irritating - it wouldn't give much time to read the result.

Thanks for your quick reply!