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

Sign Up for the IPVM Newsletter
Sign Up for the IPVM Newsletter

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.

1 report cite this report:

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...

Other Reports on General

Buying the 'Great Conversation' on Feb 29, 2016
Do not feel bad if you hear the 'Great Conversation' and think of Plato, Plutarch or Shakespeare. Sadly, a company has hijacked the 'Great...
IPVM New Features and Improvements Directory on Feb 28, 2016
IPVM's development team continuously releases new features and site improvements. This document lists those items so you can see what has changed...
IP Networking 2016 Book Released on Feb 24, 2016
The new IP Networking Book 2016 is a 208 page in-depth guide that teaches you how IT and telecom technologies impact modern security systems....
IP Networking Course Winter 2016 (CLOSED) on Feb 04, 2016
Our most popular course has all new training of network security (the top growing concern for video surveillance networks) plus improved coverage...
Network Security for IP Video Surveillance Guide 2016 on Feb 03, 2016
Keeping surveillance networks secure can be a daunting task, but there are several methods that can greatly reduce risk, especially when used in...
First Integrator Face Off Results on Jan 20, 2016
The results are in, and they are interesting indeed. Five integrators pitched us their designs in our First Integrator Face Off, aiming to solve...
Surveillance Camera Imager Tutorial on Jan 12, 2016
Imagers - CCD, CMOS, 1/2", 1/4", big pixels, small pixels, etc. In this tutorial, we explain the fundamental issues and drivers in surveillance...
IP Camera - Direct Attached vs Jack & Patch on Jan 11, 2016
An ongoing debate rages about how the IP camera cables should be terminated. This argument surrounds two common options: 'Direct Attached',...
Walmart Momentum IP Camera Tested on Jan 04, 2016
A 'Dropcam' for ~$30? Walmart does super low cost and they are now bringing it to IP cameras, with a new cloud camera for an almost impossible to...
Top 5 Video Surveillance Product Advances Going Into 2016 on Dec 31, 2015
Here are the 5 product areas that have had the most meaningful product advanced in 2015, that you should be looking at incorporating in...

Most Recent Industry Reports

BCDVideo Company Profile on May 03, 2016
BCDVideo claims better value and servers specifically selected for video surveillance, an improved experience versus working with a server...
Avigilon Is Cash Strapped, Commodity Company, Charges Analyst on May 03, 2016
Avigilon has come under attack by an analyst in SeekingAlpha charging that the company is 'cash strapped', 'becoming a commodity', with...
Software House Access Control Company Profile on May 02, 2016
In our 12th access company profile, we examine Software House's C-Cure access control platform: Comparing Software House to their...
Micropower Fails on May 02, 2016
Wireless video surveillance is a tough business. Micropower sought to deliver a wireless, turn-key, professional video solution. The most famous...
FLIR Latitude VMS Test on May 02, 2016
FLIR spent nearly $100 million on DVTel, primarily for one product - DVTel's enterprise VMS. Though FLIR has killed the DVTel brand, they are...
Camera Course Spring 2016 on May 01, 2016
This is the last week to register for the Spring 2016 camera course. Here is what is new for the 2016 course: HD analog: Expanded coverage on...
Ubiquiti Cloud Video Tested on Apr 29, 2016
  The cloud continues to expand in video surveillance. Ubiquiti's newest release offers a free upgrade adding cloud capabilities. In this test,...
Quantum Storage Company Profile on Apr 28, 2016
Storage vendor Quantum is bringing their multi-tier storage architecture to the security industry, claiming cost-effective long-term data...
Manufacturers Don't Want to 'Bad Mouth' The Competion on Apr 28, 2016
Sure, you do not want to be the like the Avigilon sales guy who said all his competitors 'suck'.  Not convincing and you look bad. However, that...
Access Control IBC International Rules on Apr 28, 2016
Dealing with fragmented local codes is one of the most frustrating parts of electronic access control design. However, the 'International Code...

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