White balance problem 5D MKII

[Danny Winn]

For some reason many times now when I try to set my manual WB I get the message "WB may not be obtained with this image". I've always had success by just taking a pic of a white sheet of paper where my subject will be then select it as my image to use, but now I get the above message. When I use the image anyway I get a horrible greenish/blue incorrect look.

Anybody know why this seems to be happening all the sudden?

Thanks.

PS: I know about all the other ways of acheiving WB , but I'd like to know why this method is giving me trouble recently;)

[Jon Fairhurst]

That typically happens when the image is overexposed.

[Danny Winn]

Originally Posted by Jon Fairhurst

That typically happens when the image is overexposed.

Weird, didnt look overexposed at all. So would you suggest lowering ISO and closing aperture for my WB image then bringing them back up after WB is achieved Jon? Is the White still White even if you mess with the exposure afterwards?

Thanks for your response Jon;)

[Evan Donn]

Enable the RGB histogram and use that to expose when you take your white balance shot - make sure none of the channels are clipping on the right. My guess is that one channel is clipping in your shot which will throw off the correction.

[Jon Fairhurst]

Hi Danny,

Evan is right. If one of the channels clips, the image can't be used for WB. Since white is technically at the clipping point, I guess it's more accurate to say that we perform "near white" or "very bright gray" balance, rather that true white balance. :)

BTW, at a Canon seminar, they said that shooting a white card gave better results than shooting a gray card. So the key is to shoot near white but to never clip.

Best of luck!

[Danny Winn]

Originally Posted by Evan Donn

Enable the RGB histogram and use that to expose when you take your white balance shot - make sure none of the channels are clipping on the right. My guess is that one channel is clipping in your shot which will throw off the correction.

Originally Posted by Jon Fairhurst

Hi Danny,

Evan is right. If one of the channels clips, the image can't be used for WB. Since white is technically at the clipping point, I guess it's more accurate to say that we perform "near white" or "very bright gray" balance, rather that true white balance. :)

BTW, at a Canon seminar, they said that shooting a white card gave better results than shooting a gray card. So the key is to shoot near white but to never clip.

Best of luck!

Awesome! Thanks guys, I can't wait to test all this out and get better results. Much appreciated;)