Color balance

or, learning to see like your camera, part 2

Let’s start by saying that color is a science. It’s a big science. It’s so big that there are entire institutes full of people so smart it makes my head hurt, all studying color. So I think it’s safe to say we’ll not be comprehensive here. We will cover the basics of color balance and differential color temperatures, as they pertain to shooting. Color management on the back end, calibrations, color profiles are for another time.

As I touched on in part 1, our brains are incredibly nimble. Vision is perception and we can adjust our perception so quickly and subconsciously that we don’t even understand it’s happening unless we look for it. One way it adjusts our perception is with variable color. Remember from elementary school when the teacher took a crystal prism and showed us how sunlight can be spread out into a spectrum?   That spectrum represents daylight broken down into it’s constituent colors (ROYGBIV.) Equal amounts of those colors combine to form what we call white light, or daylight.  

However different sources of light put out varying amounts of lights at different frequencies. For example, ordinary incandescent lights put out much more light on the warmer side of the spectrum. When we view things under incandescent light we don’t usually see this orange cast since our brains compensate for it. But it’s there, and without smart cameras, or smart photographers we would have orange photos. Digital cameras have preset color balances as well as auto white balance. A few digital cameras allow the user to set a custom white balance based on either color temperature, a visual sample, or both.

Just like auto exposure, auto color balance is good enough for most people and works well in many situations. But it can get us into real trouble when shooting under mixed lighting conditions or when trying to capture a special affect or vision. Shooting under mixed lighting sources is problematic and is to be avoided whenever possible. We can only balance for type of light at a time so if we’re trying to shoot with incandescent, daylight and fluorescent all in the same image, we’re going to be disappointed.   The way to avoid this situation is to keep all light sources of the same type, and barring that, balance the sources all to the same standard.   In other words, if you’re shooting   in a large room primarily lit with fluorescent light, but you want to supplement that light with your flash, you’ll need to manually set your white balance to fluorescent, and gel your flash green to match.   If we hadn’t gelled that flash the area where the flash was used would appear magenta by comparison.

Likewise, if shooting inside under primarily incandescent light, any source of daylight, be it a window or your flash, should be gelled orange to match.

Keeping colors balanced and avoiding mixed lighting sources and differential color temperature is one of the most important skills to master when shooting color.   Practice.

Leave a Reply

Close Menu