Training: Using a Lux Meterby John Honovich, IPVM posted on Jun 06, 2009 About John Contact John
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?"
Lower Cost Options
In addition to the LT300, Extech has begun offering lower cost compact models. The LT10 is part of their "Pocket Series", and sells for ~$60 online, less than half the cost of the LT300. However, two features are lacking compared to higher end models:
- No remote sensor: The unit is all in one, with the sensor attached to the base unit, so users cannot aim the sensor with one hand while holding the base with readout in the other.
- Claims accuracy only to 0.1 lux: By contrast, the LT300 claims accuracy down to 0.01. 0.1 is likely dark enough for many users, but not those concerned with super low light scenes.
Most Recent Industry Reports
Testing Axis' Top Low Light Camera Q1635 on Nov 23, 2015
Low light performance continues to improve, first driven by advances in image processing and now increasing number of 1/2" imagers in 1080p HD cameras. IPVM has recently tested new super low light...
Audio Analytics Aggression Tested on Nov 20, 2015
What if you could use your IP cameras to detect fights before they start? That is the goal of Louroe / Sound Intelligence with their recently released Aggression Detector audio analytics. Cl...
Pelco Optera 12MP Multi-Imager Tested on Nov 09, 2015
This summer, Pelco came out firing against Arecont, touting the superior performance of its new multi-imager line vs Arecont's. But is this really the case? We bought a Pelco Optera 180° multi...
IP Camera Bootup Shootout 2015 on Nov 04, 2015
IP cameras, like PCs, take some time to boot up. And just like PCs, the amount of time can vary greatly. Many people do not care but some people find it annoying. Perhaps more importantly, in surve...
Live From China on Nov 02, 2015
China's growing influence, if not dominance, of the global video surveillance market is unquestionable. To better understand this, IPVM has gone to China. Our first stop is CPSE, which claims ~100...
Network Cabling for Video Surveillance Guide on Oct 30, 2015
In this 14 page guide, we teach the fundamentals of network cabling for video surveillance networks, how they should be installed, and the differences in testing them for production networks. Spec...
Large Video Surveillance Systems Guide on Oct 29, 2015
This 14 page guide explains the key uses, design factors, and players in the large system surveillance market. A global group of 80 integrators responded, each offering insig...
Sony 20MP / 4K Camera Tested on Oct 26, 2015
For 18 month, Sony has been hyping 4K cameras, a year before they even announced a 4K network camera. Now, amidst intense competition and price pressure, Sony has released their long awaited 2...
ONVIF Screen Capture Tested on Oct 23, 2015
Recording a PC's screen to a VMS has several uses, but historically has required expensive dedicated encoders or specialized software for each VMS. Now, a new offering called Screen ONVIF has...
Milestone Arcus VMS Tested on Oct 21, 2015
For more than a decade, Milestone was a Windows only VMS. With the Internet shifting power away from Windows OSes, Milestone launched a new VMS, called Arcus, which can be embedded onto Linux ...