Quantity
Among all the aspects of light, quantity is the easiest to control and manipulate. In fact, most of the controls found on your camera is designed for this function. The quantity or amount of light is controlled by your camera’s ISO, shutter speed and aperture. If there’s too much light then you get overexposure and too little will leave you with underexposure.
The photo below illustrates deliberate overexposure or what is called high-key. It shows how a photo would look if large amounts of light is allowed to hit the camera sensor.
Color/Temperature
Different types of light have different colors. We don’t notice these difference so much because the human eye is designed in such a way that it will automatically negate slight color changes in light. Cameras, sad to say, are not as evolved and are susceptible to all sorts of color casts.
The color or temperature of light is measured in degree Kelvin (K) in a scale which runs from 2500K to 10000K. Light which has a higher Kelvin temperature (5000K and up) has a blue color cast to it. It is also described as being cool. Lower temperatures (2700K or below) have a yellow/red cast to it and is said to be warm.
