Perfect exposure metering. Perfect white balance.
The control card is a two-sided flexible card made of special plastic with gray and white antireflection coating.
The gray area serves as a reference area for the exposure measurement
(18% reference gray) and the white side allows for the correct white balance for digital photography.
You measure the respective side of the control card with your camera and carry out an exposure measurement or a manual white light adjustment - the camera is perfectly adjusted to the current light conditions and guarantees optimal image results.
NOVOFLEX control cards gray / white (ZEBRA) should not be missing in any photo bag.