What is color? How do we define it? How does it impact photography?
Light and color are intrinsically connected. “The word ‘photography’ is etymologically [historically] derived from the phrase ‘to draw with light’…. During image capture, light from a scene is refracted by a lens and focused on to an image plane containing a light-sensitive material [think sensor]…. Objects are visible because of the light they reflect or transmit. Colored objects appear colored because they absorb some wavelengths incident upon them and further reflect or transmit others. There are seven hues identified in the visible spectrum of Wavelengths.” These hues relate to the color of light you will get at a given time of day (combined with many other variables) and explain why we see such beautiful and colorful sunrises and sunsets. NOAA provides a nice write up on sky color: www.spc.noaa.gov/publications/corfidi/sunset.
In digital photography an RGB color wheel is used to explain how a camera captures and processes color and images. This color wheel can also be helpful in determining which colors might work well together as you look for color images. An RGB color wheel defines the primary colors as Red, Green, and Blue and the Secondary colors as Yellow, Magenta, and Cyan. These colors can be helpful in correctly processing an image when you view the processing histogram in software. See the color wheel below: