This morning I did a shoot for a dentist's office. I had to do a bunch of headshots for some of his clients and employees. My dad is in town visiting so I took him with me. Once we were set up, I had him hold the WhiBal card for a test picture.
Once I uploaded all the pictures from the shoot into Aperture 3 (which I'm loving by the way), I set the white balance for this picture using the gray card, then lifted and stamped that adjustment onto all the other pictures. Voila! Perfect white balance!