The grey card can balance the colors in your photos.
Different light sources have different amounts of red, blue and green light. Taking photographs without compensating for the color balance results in strange off-colored images. The grey card is specially colored to have an even balance of red, blue and green--combined it is grey. Use a grey card in ambient lighting to set your camera's white balance for better photographs, or use a photo of a grey card to adjust color balance in digital photo processing. The same techniques are used for still or video photography.
Instructions
1. Outdoor photos taken in the shade will appear bluish without correction.
Set the white balance of your camera with the grey card. Use the "set white balance" function on your digital camera before you start taking photographs in a new location. Point the camera at the grey card under average or typical lighting conditions for the location. Set the white balance with the grey card occupying a major portion of the image--it doesn't even have to be in focus to set the proper white balance. Use this white balance setting for ensuing photos.
2. Indoor lighting gives an orange cast to uncorrected photos.
Take a picture of the grey card in the ambient lighting. You can use the photo of the grey card to set the white balance in photo processing software to balance the colors of all photographs taken under the same lighting conditions. Load a photo of the grey card in the photo-imaging software program. Select the portion of the photo that shows the grey card and set the white balance. The photo should appear with true whites and more vivid colors. Save this setting for processing other photos taken under the same lighting conditions.
3. Proper indoor white balance restores full color.
Set the exposure on your camera. The grey card is designed to reflect approximately 18 percent of the available light. This feature is used to set the proper exposure on film and digital cameras. Setting the proper exposure (f-stop and shutter speed) using a grey card gives a good image with white objects appearing bright, and black objects appearing dark. If you set the exposure using a dark object, the camera will compensate to make the object appear grey, and it will be overexposed. Likewise, if you set the exposure on a white object, it will appear darker, or underexposed. Here is where a grey card can improve your photos.
Tags: grey card, white balance, card white, card white balance, grey card white