This does not tell me what through the lens metering is. In other words, how does it work physically? What is the definition in terms of optical physics?
I understand that the original author is not a native English speaker, but this is still a reasonably well-written article. But I'm not sure it meets the "Encyclopedic voice" criteria of Wikipedia. Statements such as "no light can reach there" and "the light was reflected down there" seem inappropriate and could use cleanup. If anyone else agrees, then the appropriate cleanup template should be applied. Donperk (talk) 03:07, 4 February 2014 (UTC)