OT: Just enter 5100K? Or white/grey balance?

OT: I am watching the Blue Crane Digital training DVD's on the 5DM2, and am learning a lot. However, they recommend a grey balance card.

I have always used a white balance card, and have been happy with the results. However, I looked at the Grey Balance card reviews on B&H, and the stills pros say grey balancing gives far superior color results than white. Does anyone know why that is?

Also, much of my video shoots are in studio. My CFL's are supposed to be 5100K (all from the same manufacturer). Can I really just enter 5100K under the white balance setting and shoot? Or is it better to white/grey balance, even under controlled lighting?

Thanks.

Norman Willis
http://www.nazareneisrael.org

From what I could glean as I researched this recently, gray cards are to stills, what white balance is to video. I agree with Michael, when we are in the field, we do tend to go for whatever we think is white. This is why I bought a set of gray, white and black cards to use to be able to set each.

During Christmas I had a GH1 here and went to white balance in the living room. Because I knew the real color of my off white chair, I was able to color balance by temp. I just kept adjusting the temp value, until my chair appeared in the screen as it really is. If you think your lighting is 5100K, I would set something in there you know the color of when it is in daylight, and try setting your cam accordingly. It might be 5100K, or as I found in my living room, it was off about 400K+ from the preset.

I don't think there is that much difference if you balance gray vs white but with white people tend to pick up any old thing that is "white" but most white things have a color tint to them. So if you use a "calibrated" gray card it would be more actuate but if you picked up and old gray thing you would have the same issue. Same would be true if you used a true white card vs a white piece of paper.

I don't think you ever go wrong with doing a true white balance. If you have the time I would stick with that. But in the end do some test and see what you like.

When shooting RAW, I've found that grey balancing tends to give better results than white balancing, even when using reference cards from X-Rite for both. I'd love to find out why grey works so much better!