Measuring Low Light Surveillance with a Lux Meter

Getting good images at night is one of the most challenging problems in video surveillance. Making this worse is that generally you cannot trust the illumination ratings provided by manufacturers.

The best tool to solve this problem is a lux meter. Lux meters provide a quantified measurement of the amount of light available. Without a lux meter, you are simply guessing. With a lux meter, you can clearly see and compare the impacts of various lighting conditions. Here is a video overview of the benefits and use of a lux meter:

Choosing a Lux Meter

There are an enormous number of options for lux meters on the market ranging from under $50 to over $500. For video surveillance, the key consideration is that a lux meter can accurately measure under 1 lux (critical for low-light and night-time testing). The cheaper consumer models usually do not do this. Based on Carl's recommendation, I selected the Extech LT300 (for $140 USD) and I am happy with it.

Benefits of Using a Lux Meter

Using a lux meter lets you determine exactly how much light you need for video that is usable for you. This is almost always far higher than what a manufacturer states as their minimum illumination.

With this knowledge, it makes it much easier to plan new camera deployments. Take a lux meter to the proposed camera site and check the light reading. You will know in advance how well it will work or if you need to use a different camera or infrared illuminators.

For more in-depth analysis and demonstrations of low light performance, see our premium report on "How Well Do IP Cameras Work in Low Light?"