Introduction to imaging

Importance of understanding light

When the sun rises in the morning and travels across the sky, the direction of light changes. This can be seen how the shadow of a tree shifts throughout the day.

In surveillance applications it is important to keep this in mind. To avoid potentially blinding backlight situations, it is always a good idea to have the sun behind the camera rather than in front of the lens.

Clouds or bad weather conditions affect the intensity of sunlight, creating a need to change exposure settings in the camera.

The time of day also affects the color of sunlight, which changes from neutral at midday to warm, intense colors at sunrise and sunset. The color of light is referred to as color temperature.

All these light parameters will affect how images are perceived. Therefore, light direction, light intensity and color temperature need to be fully understood and correctly handled in any surveillance application.

Exposure under sunny and cloudy conditions