Light comes in many different qualities and colors. Daylight can appear bluish or yellowish. Artificial indoor lighting can range from a warm, yellowish tungsten light to the greenish hue you see in offices and shops. Since the human eye does a great job of compensating for all of these different color light sources, our perception adjusts without our really noticing. However, since cameras see light literally, these subtle shifts can pose a problem.
When using film, photographers had to select a specific film type or change filters on their lenses to make suretheir whites were actually white and their grays remained gray. In some cases, a photographer might even have used a filter to artificially add warmth to an image. This process is what we now call “white balancing”.
Digital cameras make white balancing easier, but they aren’t perfect. Most include a range of preset white balance settings, such as tungsten, fluorescent, daylight, flash, cloudy, and shade. These settings are based on averages, so they don’t necessarily represent the actual lighting you are shooting under, and they can’t easily or accurately account for mixed or blended lighting.
Out-of-the-box, your digital camera’s “Auto White Balance” is pretty good at correcting for ambient light color, but it can be fooled. For example, a camera may not be very accurate at selecting a white balance under low lighting, and may even add a color cast.
The ColorChecker Passport White Balance target provides a starting point for all edits, reducing the time and effort required to get accurate color. Plus, camera previews and software histograms can be judged more precisely. Without a standard reference like the ColorChecker Passport, you’ll spend a lot more time color correcting each image manually.