Sens Up is For Suckers

Author: John Honovich, Published on Apr 07, 2012

Run as fast and far as you can, if you are looking for a good low light camera and the manufacturer cites 'Sens Up.' This is a sneaky trick that vendors play when rating low light performance. Instead of admitting that there cameras suck at night, they say things like 'min illumination only 0.000001 lux with Sens Up 512x', etc.

Let's break down what Sens Up is and how it is used to trick people.

Increasing Sensitivity

'Sens Up' implies that low light sensitivity is increased (i.e. sensitivity up - which seemingly is a good thing - who wouldn't want their cameras to be more sensitive to light? However, the problem is how this is done.

To make the camera more light sensitive, the shutter is open longer so that the camera can capture more light but there is a major downside to this.

But Blurring

The longer the shutter (i.e. exposure), the more moving objects will blur. See it below:

The image with the longer shutter is brighter but the moving person is blurred out. Bad tradeoff.

Sens Up Relative to Default Shutter

Here's how 'Sens Up' comes into play. The default shutter in most cameras is 1/30s because the default number of frames in a second is 30. To get 30 frames in a second, the shutter cannot be open longer than 1/30s for each frame.

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

Sens Up signifies how much longer a shutter is than the default 1/30s:

  • If a camera is at 'Sens Up 2x', then is has a 1/15s exposure (2 x 1/30)
  • If a camera is at 'Sens Up 4x', then it has a 1/7.5s exposure (4 x 1/30)
  • If a camera is at 'Sens Up 32x', then it has a ~1 second exposure (32 x 1/30)

The more you 'Sens Up' the brighter the image will be but the blurrier anything that moves with be. Go back and look at the 1 second exposure image above - that is 'Sens Up 32x' - unusual for most applications.

[NOTE: In analog NTSC cameras, default shutter is typically 1/60s because each frame consists of two fields. As such, 30 frames per second requires 60 fields per second. To get those 60 field, you typically need a shutter of no more than 1/60s.]

How Bad Sens Up Gets

Manufacturers often run wild with Sens Up ratings. Numerous Samsung cameras are rated with a Sens Up of 512x - which is insanely misleading:

The shutter needs to be held open for over 8 seconds (1/60s x 512) to achieve 'Sens Up 512' [note: this is an analog camera, that is why 1/60s is used]. Even a slug would be blurry at such an exposure setting. Even more crazy, this is included in PTZ specifications as well, where presumably the camera is moving.

Many many manufacturers do this - Samsung is not alone. Google results for 'Sens up 512', 'Sens up 256', 'Sens up 128', etc. return numerous results.

Beware

If you want a good low light camera, you should almost certainly disqualify any camera that lists its low light performance using 'Sens Up', it's a dirty trick used to confuse non experts into thinking a camera that is bad at low light is actually good.

2 reports cite this report:

Lux Rating / Minimum Illumination Guide on Dec 23, 2016
Lux ratings are one of the poorest specifications to use in selecting cameras. Now, with the rise of integrated IR, they are increasingly...
Shutter Speed / Exposure Tutorial on Nov 28, 2016
Surveillance users do not need to be photography experts but understanding the basics of shutter speed is critical to avoiding major low light...
Comments : PRO Members only. Login. or Join.

Related Reports

Dahua Face Recognition Camera Tested on Oct 15, 2018
Dahua has been one of the industry's most vocal proponents of the value that AI creates: As part of this, Dahua has released a facial...
Last Chance - October 2018 Camera Course on Oct 04, 2018
Today is the last day to register for the October 2018 Camera Course, register now. This is the only independent surveillance camera course,...
AHJ / Authority Having Jurisdiction Tutorial on Sep 27, 2018
One of the most powerful yet often underappreciated characters in all of physical security is the Authority Having Jurisdiction (AHJ). Often,...
Axis Vs. Hikvision IR PTZ Shootout on Sep 20, 2018
Hikvision has their high-end dual-sensor DarkfighterX. Axis has their high-end concealed IR Q6125-LE. Which is better? We bought both and tested...
IP Camera Cable Labeling Guide on Sep 14, 2018
Labeling cables can save a lot of money and headaches. While it is easy to overlook, taking time to label runs during installation significantly...
Drain Wire For Access Control Reader Tutorial on Sep 04, 2018
An easy-to-miss cabling specification plays a key role in access control, yet it is commonly ignored. The drain wire offers protection for readers...
Exit Devices For Access Control Tutorial on Aug 28, 2018
Exit Devices, also called 'Panic Bars' or 'Crash Bars' are required by safety codes the world over, and become integral parts of electronic access...
Inputs/Outputs For Video Surveillance Guide on Aug 24, 2018
While many cameras have Input/Output (I/O) ports, few are actually used and most designers do not even consider them. However, a good understanding...
Backup Power for Large Security Systems Tutorial on Aug 24, 2018
Choosing the right backup power system depends on system size. While small and medium systems greatly benefit from using UPS battery backup...
Axis First IR PTZ Tested (Q6125-LE) on Aug 21, 2018
Axis is very late in releasing IR PTZs. While competitors such as Hikvision and Dahua have offered them for years, Axis has just released their...

Most Recent Industry Reports

Best Alternatives to Banned Dahua and Hikvision on Oct 17, 2018
With the US government ban and a growing number of users banning Dahua and Hikvision, one key question is what to use for low cost? While Dahua and...
Video Quality / Compression Tutorial on Oct 17, 2018
While CODECs, like H.264, H.265, and MJPEG, get a lot of attention, a camera's 'quality' or compression setting has a big impact on overall...
Knightscope Winning Investors, Struggling With Growth on Oct 16, 2018
While Knightscope's new financials show the company only winning 11 new customers in the past 12 months, the company continues to win new...
Integrator Laptop Guide on Oct 16, 2018
This 18-page guide provides guidance and statistics about integrator laptop use. 150 integrators explained to IPVM in detail about their laptops,...
Huawei Admits AI "Bubble" on Oct 16, 2018
A fascinating article from the Chinese government's Global Times: Huawei’s AI ambition to reshape industries. While the Global Times talks about...
ADI's Financials Revealed + W-Box Growth Priority on Oct 15, 2018
  ADI is one of the most powerful distributors in the security industry but how big are they? How much profit do they make? How much do they sell...
Dahua Face Recognition Camera Tested on Oct 15, 2018
Dahua has been one of the industry's most vocal proponents of the value that AI creates: As part of this, Dahua has released a facial...
Amazon Touts Home Security Market Disruption on Oct 15, 2018
Amazon is coming for ADT and all of home security. Indeed, Amazon is advertising this as, in their own words, calling home security a: Inside...
Higher Power PoE 802.3bt Ratified, Impact on Security Products Examined on Oct 12, 2018
Power over Ethernet has become one of the most popular features of many video, access, and other security products. See our PoE for IP Video...
"New Zealand Govt Uses Chinese Cameras Banned In US", Considers Security Audit on Oct 12, 2018
Newsroom NZ has issued a report: "NZ Govt uses Chinese cameras banned in US": This comes after the US federal government banned purchases of...

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