Testing Low Light Vs Image Quality

Author: Ethan Ace, Published on Jan 07, 2013

While minimum illumination ratings imply a magical point where image quality goes from good to bad, the reality is that image quality gradually degrades as lighting levels lower. In this report, we share test results showing what this looks like and the rate of decline.

We took three well-known surveillance cameras (from Axis, Arecont and Sony) and put them side by side for a simultaneous shootout from 1 hour before to 1 hour after sunset, recording images and lux ratings at 10 minute intervals. We placed a subject carrying an eye chart at a 30 foot wide FoV. Here's an overview of the scene used:

lowering scene overview

These tests were performed at progressively lowering light levels of:

  • 7,000 lux
  • 4,000 lux
  • 3,500 lux
  • 2,300 lux
  • 1,800 lux
  • 900 lux
  • 330 lux
  • 40 lux
  • 6 lux
  • 3 lux
  • 2 lux
  • 1.5 lux
  • <1 lux

The minimum illumination ratings of each of these cameras also varied, as follows:

  • 3.1 MP Arecont: 0.3 lux color/ "Day/Night: 0 Lux, IR sensitive"
  • 1080p Sony: 0.4 lux color/0.25 lux black & white @ F1.2
  • 720p Axis: 0.4 lux color/0.06 lux black & white @ F1.2

Did these lux ratings hold true? Ha!

Overview / Key Points

Image quality fell modestly when light levels were over 500 lux, but then started to drop significantly from the 300 to 3 lux levels. All of the camera experienced significant visual quality loss far above their rated lux ratings.

This image shows a comparison of seven decreasing lux levels, for reference (click for full size):

Side by side lux levels

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

Lux Level Examples

Official sunset on the day of this test was at 4:51 PM. We set our scene at 3:50 PM and began recording starting at 4:00. At this time, the day was still very bright at over 7,000 lux. All cameras displayed clear video with little noise.

4PM

At 4:10, the results were approximately the same, with light levels dropping to about 4,000 lux.

4:10

At 4:20, dropping down to ~3,500 lux, the 3.1 MP camera began to display a notably dimmer image, while 1080p and 720p models remained fairly close to earlier ones.

4:20

At 4:30 PM, at ~2,300 lux, results were similar to the previous, with little change in any image quality.

4:30

Little change at 4:40 PM and ~1,800 lux:

4:40

Around sunset at 4:50 PM and ~900 lux, close inspection reveals visible noise beginning in 3.1 MP and 1080p cameras, though not a lot:

4:50

5:00 PM, at ~330 lux, continues this with noise more pronounced especially in the 1080p camera. At this point, light levels were reduced by about 95% from our starting point of 7,000 lux.

5:00

As the sun continues to set at 5:10, down to just ~40 lux from ~300 lux ten minutes prior, we see a jump in visible noise in the 1080p camera. The 3.1 MP and 720p models remain pretty steady, with the 720p camera only modestly dimmer than when the test began.

5:10

At 5:20 PM and ~6 lux, the 3.1 MP model switches to night mode, the first camera to do so, at around 6 lux. Noise continues to increase in the 1080p model, and sharply increases in the 720p camera, both still in color mode.

5:20

At 5:30 PM and ~6 lux, the increase in noise in the 720p model begins to negatively impact our ability to recognize the subject. The 1080p camera has cut over into night mode at this point, and noise is somewhat lower than in the previous color image.

5:30

Noise continues to increase in the 720p image at 5:40, with the camera still in color mode at ~2 lux. While dimmer, the 3.1 MP and 1080p models provide approximately the same image quality as at the prior light level.

5:40

The 720p camera finally switched to night mode at 5:50, though noise remains constant. At this point, the sun had fully set, with outdoor lighting providing a constant 1-2 lux scene.

5:50

Switching off the outdoor lights, the light level drops below 1 lux. The subject is still detectable in the 3.1 MP and 720p cameras, though details cannot be made out. The 1080p camera provides no usable footage of the subject at this light level.

No outdoor lights

Methodology

Key steps for setup included:

  • All cameras were reset to factory default.
  • Shutter speed was standardized to 1/30s.
  • Auto back focus was run on the 720p and 1080p cameras, but was not supported on the 3.1 MP model, which was manually focused.
  • Day/night cutover settings were left defaulted. This resulted in all cameras cutting over at differing times, as can be seen in the images.

The specific models used were an Arecont AV3116DN, an Axis Q1604 and a Sony SNC-CH240.

5 reports cite this report:

Calculating Video Surveillance Storage / Bandwidth on Dec 29, 2016
Calculating surveillance bandwidth is complex, and inexperienced users can easily underestimate bandwidth, leading to reduced storage durations...
Camera Coverage Areas on Feb 10, 2016
How wide and far on an area can a camera cover?  A fundamental metric in analyzing this is pixel density (aka PPF or PPM). Three key factors...
Video Surveillance Commissioning / Install Checklist on Feb 08, 2016
This 60+ point checklist helps end users, integrators and consultants verify that video surveillance installation is complete. It covers the...
Avigilon Real Time Exposure And Gain on Feb 24, 2015
Knowing how exposure and gain impact image quality, bandwidth, and camera performance can useful in installation and troubleshooting. Very few...
How Well do IP Cameras Work in Low Light? on Jun 06, 2009
[2016 Update: Camera technology has changed substantially since 2009. The same pattern occurs but cameras are generally much better in low light....
Comments : PRO Members only. Login. or Join.

Related Reports on Low Light

Axis Laser Focus PTZ Tested on Aug 14, 2017
Axis has been touting its new Q6155-E laser focus PTZ as 'always in focus' and 'always in color'. Does it really deliver? We bought and tested...
IP Camera Specification / RFP Guide 2017 on Aug 14, 2017
RFPs are hard. Do them 'right' and it takes a lot of knowledge and time. Do them 'wrong' and you can be (a) unwittingly locked into a specific...
ADI 'In The Dark' About Low Light on Aug 07, 2017
ADI's recent post on 'How To See Better In the Dark' makes basic mistakes, promoting outdated technical claims. Missing: Super Low...
Dahua 4K Turret Tested Vs Hikvision (N84BG44 ) on Aug 02, 2017
Dahua has released their latest low cost 4K model, the N84BG44, claiming Smart H.265+ and 50m IR range. We bought and tested this new model against...
Super Low Light Surveillance Guide on Aug 01, 2017
At the beginning of this decade, low light performance of megapixel cameras was generally terrible. This was the era of super slow shutter where...
IR Surveillance Guide on Jul 31, 2017
Infrared (IR) has become an increasing core component to video surveillance systems. In particular, the expansion of integrated IR cameras that...
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...
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...

Most Recent Industry Reports

Final Day Save $50 - IP Networking Course September 2017 on Aug 17, 2017
Today, Thursday, August 17th is the last day to save $50 on the September IP Networking Course. This is the only networking course designed...
Directory Of Consumer Security Cameras on Aug 16, 2017
The consumer camera segment continues to grow, with new startups and models from existing players released seemingly every month. In this report we...
Cat 5e vs Cat 6 vs Cat 6a Network Cable Usage Statistics on Aug 16, 2017
Cat 5e? Cat 6? Cat 6a? What do integrators use in practice, today? 140+ integrators told IPVM. Here are the results: For those who want to...
Hikvision Responds To Cracked Security Codes on Aug 15, 2017
Hikvision has responded to IPVM's report on Hikvision's security code being cracked, both with a 2 page update to dealers and communication...
Stolen Video NVR / DVR Statistics on Aug 15, 2017
"But what happens if someone steals my recorder?" Anyone who has done more than a handful of jobs has probably heard this question several times....
Hikvision Europe Cutting Out Unauthorized End User Sales on Aug 15, 2017
The days of anyone buying Hikvision from anywhere off the Internet are numbered, at least in Europe, if Hikvision's plan comes to fruition. In...
Axis Laser Focus PTZ Tested on Aug 14, 2017
Axis has been touting its new Q6155-E laser focus PTZ as 'always in focus' and 'always in color'. Does it really deliver? We bought and tested...
Vulnerability Directory For Access Control Cards on Aug 14, 2017
Knowing which access credentials are insecure can be unclear, especially because most look and feel the same. Even the most insecure 125 kHz types...
IP Camera Specification / RFP Guide 2017 on Aug 14, 2017
RFPs are hard. Do them 'right' and it takes a lot of knowledge and time. Do them 'wrong' and you can be (a) unwittingly locked into a specific...
Cellphone Usage Issues For Integrators (Statistics) on Aug 11, 2017
Cellphones clearly offer significant advantages in communication and problem solving. But they can also be a major pain point if employees...

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