Hi,

at what point does the 10D register the WB reading when set in AWB mode. Is it when one half depresses the shutter release button to focus and expose?


Cheers
Andrew

Hello Andrew,
Good question. The camera adjusts for white balance after the shot is captured but before it's recorded. That is, it's part of the suite of in-camera processes that the raw sensor data undergoes on its way to becoming a JPG. RAW format processing bypasses such settings as white balance and sharpening.

Thanks Ken

That's a very good question. My best guess is the measurement of the color temp is taken at the same time the exposure is determine, when the shutter button is depressed half way. However, this could possibly be changed, depending on the camera your using. Some cameras have a custom function that can change the exposure determination moment via a menu setting. I normally shoot RAW and WB can be less of a concern, over jpeg, during shooting, because of the post processing workflow Ken mentions.