Simply put and as it pertains to security cameras, a lux rating is a way of determining a cameras ability to see in various degrees of darkness. It’s very important to note that lux ratings for IR cameras are rated differently from cameras without that Infrared capability; be careful not to compare these two side by side as they are going to need to be interpreted differently.
Infrared Camera Lux Rating
A camera equipped with an Infrared board is clearly going to be able to see in complete darkness. The lux rating in the case of a camera like this is based on its ability to see in the dark with the assistance of its Infrared board. For this reason, any camera that has an Infrared board will have a lux rating of zero; zero indicates that it can see in complete darkness.
Any camera absent an IR board is going to be solely reliant on any and all available ambient lighting. That makes paying attention to these types of cameras much more important. Depending on how well or dimly lit the area is that the camera will be monitoring will determine which one of these cameras and it's lux rating is going to be sufficient. Here’s a basic chart to help:
|0.0 lux||Complete Darkness|
|0.0001 lux||Night, Overcast|
|0.002 lux||Night, No Moon|
|0.3 lux||Night, Moonlight|