Many of my photos are shot without use of an underwater strobe/flash/artifical light. I use a specialty card I created to set a reference point for the rest of the photos on the dive.
The custom profile created from using the card for photography allow me to rapidly edit all my photos, and get extremely accurate color correction.
For video work, the top section of the card can be used to set a perfect white balance, again greatly reducing the time to color grade footage in post.
For a walk through on how I use the card in my post processing workflow please see this video:
