Sensitivity and lux measurements for our cameras
Last Revision Date: 2/9/2016
This article provides a general discussion of lux ratings and how they pertain to our cameras.
As defined by the International System of Units (SI), lux is a measure of illuminance. One lux is equal to one lumen per square meter. The lux value of a camera represents the minimum illumination the camera requires to capture an "acceptable image."
We do not provide lux ratings for our cameras because:
- The specifications are not well defined.
- The rating can vary significantly between vendors and camera types for a number of reasons:
- There is no standard lux test and measurement method for digital cameras. While there are standards for analog cameras, these do not generally apply to digital cameras.
- Analog cameras are measured at fixed video rates of 30 or 25 FPS at video resolution. Digital cameras have much wider varieties of resolutions and frame rates (or exposure times).
- Most testing is done with visible white light and does not show the sensitivity outside the visible spectrum or at a specific wavelength.
- Gain of the cameras can vary significantly between camera models. This makes it very difficult to compare the 0 dB gain or maximum gain of cameras even when they use the same sensor.
Instead of using lux to measure and report the sensitivity of its cameras, we use metrics defined by EMVA1288. Each measurement is characterized using an internationally recognized method defined by this standard, providing an objective performance comparison between different cameras.
Comparisons may also be made between cameras from different vendors if the vendors adhere to the EMVA1288 methods of measurement. For more information on the EMVA terms and their meaning, see EMVA 1288 Overview: Imaging Performance.
Specifications of each of our cameras are found on the web page for that camera model.