Sensitivity To Light (Lux)

As understood, the intensity of light is essential for a good image. But, producing high intensity light is very expensive and hence it is desirable to have highly sensitive camera systems that can pick up the image with minimum illumination. Light sensitivity is measured in units called Lux. Thus, to put it in other words, we desire a camera system that produces a good image even with minimum-Lux light. Thus, we actually desire more sensitive camera systems. The minimum illumination required is a function again of the design of camera and is controllable by the manufacturer.

A noteworthy issue that deserves a mention here is that comparison of sensitivities of camera systems cannot be done purely on Lux factor. It is equally important to compare Lux from a specific constant distance without which the figures hold no good. Thus, sensitivity should be expressed in Lux/Foot Candle where foot candle implies when a candle is placed at a distance of 1 foot from the chip. This distance may vary but has to be held constant when comparing two different systems. Thus, when one says that his/her camera has light sensitivity of 1.5 Lux while someone else’s has 2 Lux and hence his/her camera is more sensitive is a misguiding statement. On the other hand, if he/she says that the sensitivity of his/her camera is 1.5 Lux at 1 Foot Candle while that of the competitor is 2 Lux at 1 Foot Candle and hence his/her camera is more sensitive, then the statement is correct.

Taken in toto, all the above four specifications in a camera system together give an indication of the overall quality of the camera system.