The Polaroid Digital Grey Card Set features a digital grey color reference card, a pure white color reference card, a true black color reference card, a user's guide and a lanyard with a detachable clip. Get perfect exposures every time with this accessory.
By using this set of three cards - black, white and neutral grey simply take a picture of the card in the same lighting your subject is (or was) in. Use auto white balance and P (Program) mode for the picture. You can either use the resulting picture as the basis for a custom white balance setting, or you can use the card set picture during post processing for a custom white balance finish.