White balance is the cornerstone of color management. Although most modern digital cameras have excellent auto white balance nothing compares to customizing your camera’s white balance manually.
Before demystifying the process of white balancing your camera manually it is important to understand the fundamentals of what white balancing is; and its importance in creating superlative images. White balance first introduce was first introduced to us when video cameras replaced movie (film) cameras . Since the vidicon tube and eventually the CCD and CMOS chips are electronic they require a reference point for color.
The positive primary colors are Red, Green and Blue; when equal amounts are combined (see RGB Spectrum diagram) they create white. Negative primary colors are Cyan, Magenta and Yellow, which when combined make black (CMYK). With digital cameras capturing RGB file information you can see why white is the reference point. The white point is used to adjust and render specific colors – particularly neutral colors – correctly; hence, the general method is sometimes called gray balance, neutral balance, or white balance. Color balance changes the overall mixture of all colors in an image.
Before digital cameras were introduced, we used emulsion based films not sensors to capture images. There are only two types of film, positive and negative. Yes, photography is algebraically based! Both produced first in black and white and then color. Most people are unaware, but positive color film (slide film) goes through two development stages; and, although it is a color film, after the first development is completed the film looks like a black and white negative.
Light Balancing Correction Filters
Unlike most of today’s cameras that are programmed to do the thinking for you; photographers used to rely on film type for for light sensitivity (ISO/ASA) and color management that was far more complex than today as your choice was film balanced for either daylight (5500 degrees kelvin) or tungsten light (3200 degrees Kelvin). This means if the film you were exposing doesn’t match the type of light you are using you would have to correct the color by placing a filter over your light source or your lens.
When shooting daylight film with a florescent light source you need either a purple FL-W or FL-D florescent conversion filter. This will correct the nasty green cast of florescent lights; and can be used to turn an otherwise gray sunset an exciting violet. If you were shooting tungsten film with florescent light you would use an FL-B filter.
So, how do you white balance? Obviously in today’s world we can correct color temperature quite easily with the proper image editing software, and with the use of a Promaster White Balance Lens Cap Filter. Like any other white balancing filter it is much easier to use than you would think. Simply place the filter on your lens in place of the lens cap and aim the camera to the area you are going to be photographing and fire the shutter.
Now select your camera’s setting to Custom White Balance and select the image you created with the filter and click ok. Remove the lens cap and begin exposing images with great color balance!