How Much Frame Coverage for Custom White Balance?

[BobbyMurcerFan]

I have a D5200 and have been getting inconsistent results with the manual white balance, a.k.a. PRE Preset manual. I think it has to do with how much of the frame the white card is filling up. Is there a rule of thumb for how much frame needs to be filled by the card you are white balancing off of? THANKS!!

 

[Samuel H]

I don't have one with me right now, but IIRC it has to be the full frame. Easy to test, anyway: find a bright-colored background, and test it with the card filling almost all of the frame but not quite. Or find a white wall and a bright colored object, and do custom wb with the wall filling all the image, and the color object appearing on one side.

Sony seems to be the one making custom WB work the best: not only is it probably the most consistent and accurate I've used, but the white card only needs to fill a tiny portion of the center of the image.

 

[Sumfun]

In the D7100, you can also do spot white balance in live view mode. The camera only looks at a small spot in the image, and you can move the spot around the screen.