Don't Trust Lux Ratings

Author: John Honovich, Published on Jan 09, 2013

Do not trust lux ratings. Do not use lux ratings to specify cameras. Period.

Lux ratings are widely, and unfortunately, used to define low light performance, with the lower the lux rating, the stronger low light performance. Here's what this commonly looks like on manfacturer specifications:

lux ratings examples

For instance, a camera with 0.02 lux is supposedly 'better' in low light than a camera with 0.05 lux. (Background - See our Lux / Lux Meter Tutorial).

[New Test Results show the reality of low light image quality.]

However, they are so riddled with fundamental problems that lux ratings must be abandoned.

Widespread Misconception

In regular IPVM assessments, we find easily half of surveillance professionals believe and use lux ratings as a viable metric for assessing low light performance.

More importantly, lux ratings are overwhelmingly used in RFPs to require specific low light performance. Cameras that do not meet the RFPs lux ratings specification are rejected.

The Fundamental Problems

Get Video Surveillance News In Your Inbox
Get Video Surveillance News In Your Inbox

Here are the fundamental problems:

  • Unrealistic numbers
  • No standard process
  • No revelation of what image looks like
  • Failure to disclose camera settings
  • Gradual image quality decline

Unrealistic Numbers

Most manufacturers have lux ratings that are incredibly unrealistic, with ratings of .001 lux or lower common. However, that is incredibly dark. Almost any camera truly in such conditions in the real world would capture nothing or be so dark and noisy as to be practically useless.

No Standard Process

Each manufacturer measures on their own, by themselves and with whatever 'standards' that they like. As such, it is impossible to compare the results of two manufacturers without more knowledge or testing of one's own.

No Revelation of What Images Look Like

No manufacturer ever releases images of what their cameras look like at their claimed lux ratings. Almost certainly, the images would be terrible.

Failure to Disclose Camera Settings

Many manufacturers use tricky settings such as using super slow shutters and fostering tricks like 'sens up'. Often they will obscure this in their specification, resulting in seemingly eye popping low lux ratings like 0.000001 lux.

Gradual Image Quality Degradation

The image quality of all cameras gradually declines as light levels fall below 50 lux, with falling signal to noise ratios, and increasing gain control levels. There is no magical point where quality turns from good to bad.

Consultant's Fault

The lion's share of the blame goes to consultants who regularly specify cameras based on minimum illumination specifications though they rarely if ever test to verify that the ratings are accurate.

Manufacturer's Trapped

This creates an ugly system where even the most ethical and responsible manufacturers are trapped. The first manufacturer to 'tell the truth' about their low light performance will be disqualified from many large projects. Because of this, no one can afford to do so.

Worse, it rewards the most unscrupulous vendors who realize that they are rarely, if ever, called on their specs.

What To Do?

The best way is to test cameras head to head in the same conditions with the same fundamental settings (especially shutter speed). For example, see our MP low light shootout. Take your finalists and place them for an evening in your desired deployment location. I can almost guarantee that the results will not match what the lux ratings suggest.

Short of that, a few specifications do deliver:

  • F Stop: While small differences in F numbers (1.2 vs 1.4) have limited practical impact, going from F1.2 vs 2.4 typically has a major impact on low light quality.
  • True Day/Night: Cameras with mechanical cut filters consistently deliver notable increases in low light performance.
  • Adding IR: If a scene is quite dark and you want to ensure maximum illumination, consider adding IR either through integrated IR or add-on illuminators.

There is no magic number. Unfortunately, lux ratings are voodoo, more smoke and mirrors than reality. Let's move past them and focus on better metrics for reliably specifying high quality low light performance.

2 reports cite this report:

4MP Low Light Weakness Tested on Jul 19, 2016
4MP cameras are an emerging force in video surveillance, with many manufacturers now focusing on 4MP as their new high end, surpassing...
Surveillance Camera Specification Guide on Aug 19, 2013
Anyone reviewing RFPs knows there are countless common problems, with 'good' specs seemingly few and far between: RFPs copied from more than 10...

Related Reports

Hikvision H.265+ Bullet Tested (2035) on Jul 24, 2017
Continuing our tests of Hikvision's new low cost Value Plus line, we bought and tested the 3MP DS-2CD2035FWD-I, now including H.265+. We shot the...
Axis Door Station Tested (A8105-E) on Jul 19, 2017
Axis continues their push into niche markets, especially audio, with network speakers, an IP horn, and video door stations. We bought and tested...
March Networks Company Profile on Jul 17, 2017
March Networks was one of the most well-known video surveillance manufacturers of the 2000s. In 2012, March was acquired by Chinese / American...
Nest Cam IQ Tested on Jul 10, 2017
Nest has released their latest entry in their camera line, the Nest Cam IQ, touting 4K "Supersight", facial recognition, "HD audio", invisible IR,...
Uniview Low-Cost Bullet PTZ Tested on Jun 21, 2017
Uniview is offering a HD zoom bullet camera, the IPC742SR9-PZ30-32G, with an integrated pan / tilt positioner, for the price of a low-cost...
Axis P3225 Mk II Tested Vs. Original on Jun 20, 2017
Axis has released a number of 'Mk II' versions of their cameras, which are the same fundamental camera but with specific improvements. We tested...
VMS UI - Light vs Dark Preferences on Jun 16, 2017
Several VMS manufacturers have the ability to choose a user interface with either a light or dark color theme. 150+ integrators told us which they...
Axis 20MP Q1659 Camera Tested on Jun 13, 2017
Axis has joined the super high resolution camera trend with their Q1659, a 20MP model equipped with Canon's APS-C sensor. We tested the Q1659...
Avigilon Announces New Lowest Cost Camera (Mini Domes) on Jun 06, 2017
Avigilon's first Micro Dome (see IPVM's test) is now 4 years old. Since that time, low-cost fixed focal Chinese manufacturer dome usage has...
Samsung SmartCam A1 Totally Wireless System on Jun 06, 2017
Hanwha is keeping the Samsung brand alive in consumer cameras with the SmartCam A1, a new offering combining an autotracking 1080p camera with base...

Most Recent Industry Reports

Hikvision H.265+ Bullet Tested (2035) on Jul 24, 2017
Continuing our tests of Hikvision's new low cost Value Plus line, we bought and tested the 3MP DS-2CD2035FWD-I, now including H.265+. We shot the...
Sports Stadium Security Design Recommendations on Jul 24, 2017
Sports stadiums pose many challenges for designing security systems. The facilities vary from being mostly vacant, to packed with tens of thousands...
Competing Against Convergint on Jul 24, 2017
No integrator is more aggressively expanding than Convergint Technologies. Owned and funded by private equity firm KRG, Convergint has acquired...
Security Robots Are Just Entertainment on Jul 21, 2017
Great entertainment, no real security value.  That is the happy (or sad) state of security robots in 2017. Knightscope robot's drowning, the...
Wireless Burglar Alarm Sensors Guide on Jul 21, 2017
Wireless sensors for burglar alarm sensors are an increasingly common option for the historical labor intensive wired alarm systems. However,...
Competing Against ADT on Jul 20, 2017
ADT is one of the biggest players in the security industry, with ~$4 billion revenue. In 2017, they were acquired / merged with Protection...
Hikvision Launching Deep Learning Recorders on Jul 20, 2017
Hikvision has become a common choice for super low cost NVRs. Now, Hikvision is aiming to move up market, with deep learning NVRs that claim far...
PR Campaign Exploiting Manufacturer Cybersecurity on Jul 20, 2017
Manufacturers increasingly have a bulls-eye on their back. As cyber security solutions providers grow, they realize a great way to get publicity...
Axis Door Station Tested (A8105-E) on Jul 19, 2017
Axis continues their push into niche markets, especially audio, with network speakers, an IP horn, and video door stations. We bought and tested...
Manufacturer Favorability Guide on Jul 19, 2017
This 120 page PDF guide may be downloaded inside by all IPVM members. It includes our 20 manufacturer favorability rankings and 20 manufacturer...

The world's leading video surveillance information source, IPVM provides the best reporting, testing and training for 10,000+ members globally. Dedicated to independent and objective information, we uniquely refuse any and all advertisements, sponsorship and consulting from manufacturers.

About | FAQ | Contact