Surveillance Camera Imager Tutorial

Author: John Honovich, Published on Dec 23, 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 camera imagers, including:

  • Sensor vs Imager
  • CCD vs CMOS
  • Imager Manufacturers
  • Camera Manufacturer Imager Disclosure
  • Imager vs Resolution
  • Imager Size
  • Pixel Size
  • Imager vs FoV Width
  • Imager vs Low Light Performance

Plus, we provide a 7 question quiz at the end to test your knowledge.

******* - ***, ****, */*", */*", *** ******, ***** ******, etc.

** **** ********, ** ******* *** *********** ****** *** ******* in ************ ****** *******, *********:

  • ****** ** ******
  • *** ** ****
  • ****** *************
  • ****** ************ ****** **********
  • ****** ** **********
  • ****** ****
  • ***** ****
  • ****** ** *** *****
  • ****** ** *** ***** ***********

****, ** ******* * * ******** **** ** *** *** to **** **** *********.

[***************]

Sensor ** ******

******** ****** ************* **** ***** ********** '******' ** '******'. **** ********* to ************ *******, **** **** *** **** *****, ******, ***********, an ****** ** * ******** **** ** ******. ******* ** this, ** **** ********* ***** ** '******' **** ******** ***** surveillance *******.

CCD ** ****

*** *** **** ********** ***** ** ******* **** **** *** and ****.

*****, ** ****, ********* *** ************ ******* *** ****, **** the **** '****' ** *** '*****'. **** ** *** ******** of * ****** ***, **** *** ******* **** *********** *** CMOS *** ****** **** **** ** * ***** ****, ***** quality ***********.

******* *** **** *** ******, * ********* ******* ******* ****. However, **** ** *****, ********** ***, ** * ********* ******, impossible. ** *** **** ****** *** *******, *** ***** ********* almost *** ****** ************ *******, ********* *** '***' ****** *** models.

Imager *************

***** *** **** * *** *********** ************* ** ************ *******, with *** **** ********** ***** *******************,********* ****. **** ****** *************, ****** ************* ***** * ***** ** models **** ******* ****, *** **********, ***** **** *** *** ************, to **** * ***.

Camera ************ ****** **********

****** ************* ********* ******** ****** ************ / ****** **** ***, ** ** ** not **** ** ******* *** ******* ***** ** ***** *******. **** will **** *** ****** ************ *** *** *** ******** *****. For *******, **** ** *** **** ** *** ** **********, Omnivision ***** ****** ** ******* **** ******* ***** / *********** tradeoffs. ********, **** ** *** **** * ******* **** ***** the ***** **** ****** (***** ** ****, ** ********), *********** in ******, ******** *** *********** ***** ***** ****** ** ********** quality ***********.

Imager ** **********

******* **** ** *** ******* ********** **** *******. **** ********** the ******'* ******* **********. **** ******* *** *** ** ***, 1.3MP, ***, ***, ***. ********, ** / **** ******* **** emerged ***** ** ******* ** ****** ** *******.

Imager ****

******* *** ***** **** ********* ***** (*.*., *****) ** ********* small (*.*., **** ******). ************ ****** ******* **** ** **** in *** ******, ******, *** ********* ******, **** **** ***** imagers.

*** ***** ***** ***** *********** ****** ****. *** *** ****** ones ** *** **** *** ****** *** ******** *** ************. The *** ** *** ***** (*/*.*") ** ******** ***** ****** large *** ******* ************ *******:

**************, **% ** ******* **** ******* **** *** ******* */*" and */*". *** **** ****** ****** **** ** ************ ** ~1/3", **** */*.*" *** */*.*" ******. **********, ***** ********** ****** (720p/1.3MP *** *****) ***** **** ******* */*" *******, *** **** these ****** ************* *** */*" ******* *****.

********** ****** ****

**** *** **** *** *****, *** ******* ****** **** *** increased **********. ** *********** ********, ***, ***, ***, **, ***., imager ***** ****** **** */*" *** ********** ******** **** ******.

**** ** */*" ***** *******

*** **** ********* ****** ***** ** ****** **** **** ** the **** ** */*" ***** *******. **** ************* *** **** at ***** *** "**** ***" ***** ***** * ~*/*" (** 1/1.8", */*.*", ***.) ******, ******** *** ***** *** *****. 

****** **** */*" ***** ****

******* ****** **** */*" *** ***** **** **** ** ************, with **** * ******* ** *******. ********'* *** ****** ** best ***** *** ***** *** ** ***** ******* (**.***/~*.**"), *** others **** ****** ********* ** **** *********, **** ******'* **** *****, *** *******/***** ***-* *********** *** ****.

Size **********

****** ****** ************, ****** **** ** ****** ****** ********* ** camera ************* ** ************* ******. **** ** ** ******* ** the ***** ** ****** ********* ********:

Pixel ****

******* **** ** *** **** ** ***** ******, ******** ** microns. 

***** **** ** **** ******** ********** ** ****** **** *** number ** ****** (*.*., **********). *** ****** *** ******, ********** else *****, *** ****** *** ***** ****. *******, ** *** add **** ****** (*.*., ***** **** ** ** **) *** the ****** **** ***** *** ****, *** ***** **** *********.

****'* ** ******* **** ** ****** ************* ******* ****** ****, resolution *** ***** **** **** ** ****:

**** ****** ****** ***** ***** *******, ********** **** *****, * larger ***** *** ******* **** *****, *** ********* ******* ******** / ****** *** ***** ******. *******, **** ***** ******* ****** low ***** *********** ** ** ** *** ****** / **** to ******** *** ****** ** ****** **** ******* ***** ** pixel ****.

****, ***** **** ** ****** ***** ********* ** ****** *************, so *** **** *** *** ** ** ******** ** ******* at *** ********** *** ****** **** ** **** *****.

** ***** ****

** ******* *** ************ ******. ******** **** **** ~** *** pixels ** ***** ******* *** ** ****** ******* *** ********* larger **** *****, ********* *** ***** **** *** ** ******* ** *******. This *** **** *** ***** ***********. ****, ** ** ******* further, ****** ** ***** ********** **** **** ** *******.

Imager **** ** *** *****

****** **** *** * ****** ****** ***** *****. *** ******* *********** ** *** ** **** ****** (*.*., 3mm, ****, ****, ***.).

*******, *** ****** *** ******, ********** **** *****, *** ****** the ***.

** *** ***** ****, ****** ***** ** ************ ** *** vary **** ****, ** **** **** ******* ********* ****** *****, *** FoV **** ******* **********. *** *******:

** ****, ** ********* ** *** * ***** *******, *** is ***** ***** ***** **.

Imager ** ******

******* **** ******* ** ** **** *********** ***** (*.*., *.***,*****, ***.). ******* *** ********* ****** ***** ******* ** **** they ******* *** *** ****** ***** *** ***** ************ ** the ** ******* / ****** ** * **** (***) ** perform ****. 

Imager ** *** ***** ***********

******* *** ** ****, *** *********, *** **** ******, ****** in ******* ** **** ****** ******* ****** ******* ****** *** light ***********. ****** ****** ******* ****, ***** *** ***** *** drivers **** ********* *** **** *********, ****** *** ***** ***** processing **** ** **** ** *** ******* / *** ** the ******. **** *** ***** **** ** ********* **** ** *** ***** *********** *****.

*******, *** ***** */*" ***** ******* *********** *** *** ******** ********* ****** **** *** *** */*" ***** *******, ** these ****** ********* ***** *** **** (** ******) ********** **** in */*" ****** ** ****** */*" ******* **** ****** ***********, resulting ** ******* ****** ***********. *** *** ***** ** ****' */*" ***** *********** ********* */*" *************** ***********, *** ******* */*" ******* *** ****** *** ********.

************, ***** *** * ****** ** */*" ****** ******* ********* ******* image ********** **** *** ***** **** ** *** *****. ****, a ****** ** ** ******* **** */*" ******* ** ******, but *** ***** *** ** *** ***** ******* *** ***** size ** ****** ***** *** *** ******* **** ** **** the ********** ***** ** ******* **** ***** ***********.

Quiz ********

**** *** * ******** **** *** *** *** **** *** know *******

Updated ****

**** **** *** ********** ******** ** **** *** *** ******* in **** ** ******* ************ ** */*" ******* *** ** cameras.

Comments (9)

Hi, I want to share the following information; as far as I know, increasing the pixel size will decrease the spatial resolution. I'm quoting form the following link "Images having higher spatial resolution are composed with a greater number of pixels than those of lower spatial resolution"

http://micro.magnet.fsu.edu/primer/java/digitalimaging/processing/spatialresolution/

"increasing the pixel size will decrease the spatial resolution"

That's true, assuming the imager size stays the same, simply because the total area is constant but the size of the components (i.e., pixels) have expanded. Bigger pixels in the same space means fewer total pixels, i.e., spatial resolution.

Btw, this is a tautology:

"Images having higher spatial resolution are composed with a greater number of pixels than those of lower spatial resolution"

This is true, by the definition of spatial resolution. However, it does not mean it has better image quality - Pixels Determine Potential, Not Quality

In surveillance, 95% of cameras have imagers that are between 1/2" and 1/4". The most common imager size in surveillance is 1/3".

Is that the horizontal size or diagonal size, or area?

The imager size is convention, not an actual measurement.

From the wikpedia page on image sensor format:

"Sensor formats of digital cameras are mostly expressed in the non-standardized "inch" system as approximately 1.5 times the length of the diagonal of the sensor. "

For example, a 1/4" imager has a diameter of 4mm (or .157 inches). Multiplied by 1.5 gives nearly 1/4".

Here's an excerpt from the wikipedia table on imager size dimensions:

So it's kinda like a shared fairy tale that all the manufacturers tell round the campfire? Who gets stuck holding the "short end" of the stick?

At the risk of being pesky, there is a mighty odd thing going on there in that thar chart, where whenever the inch size denominator is an integer, the diagonal measurement is an integer too, but in mm. I can't think of how the heck that could happen except by chance?

One more for the road, does that mean that a 1/4" sensor is will always be having the same aspect ratio, or is that chart just a one example of what it could be? Thanks for the lesson.

Jim, I'm a little surprised at your surprise; after all you were the first person to answer a similar question correctly, (though looking back, you did say you "cheated" :)

I never really found a satisfactory answer to how it came to be, but I don't think it's to 'hoodwink' anybody. What I did learn was that 'back in the day' , way before IP cams, the CCD sensor was surrounded by some kind of vacuum tube (help tube expert!) thingy that made the diagonal size of the whole component "1/4 or whatever. But of course the active sensor size was smaller. Then they stopped using the tubes, and started making smaller packages, just because they could.

My guess us when that started, they had to agree on the active dimensions of the old packages, and for some reason (help, fab expert), did that in mm. And that married the even inches to the even mm. Maybe John or somebody knows more. But its just history that's unimportant now, and like Brian basically said the only thing you need to know is you is that you don't know the exact size by the fractional inch thing, its just a convention.

****Quiz Spoiler alert****

Pixel size is the best metric to gauge low light performance.

Objection: the explanation to the answer does not give us any better metric than pixel size, saying

Pixel size is rarely disclosed, so it is hard to use as a metric. One can estimate it by contrasting resolution and imager size.

But since resolution and imager size are almost always present, one can almost always derive it thru simple division. Or add the calculation to the camera calculator, it's as easy as PPF.

However, even with that, low light quality varies greatly depending on image processing

Image processing is not a metric.

and integrated IR usage.

Most cameras, according to the finder, do not have IR, and therefore this might be hard to use as a metric.

Also, strictly speaking IR removes the low-light condition by adding (IR) light. In the case of the (few) cameras with integrated visible light, we would probably not say it had 'good low-light performance', rather we would say it had a 'good light'.

Did you have another metric that is better than pixel size?

On the other hand, imager sizes in surveillance do not vary that much, so even with notably different imager sizes, the FoV only changes moderately.

Just to note, the change in FoV width is directly proportional to the change in sensor width, and inversely to focal length. In the example, a 1/3 format sensor has 75% of the width of a 1/2 format sensor.

With an imager twice as wide you would have a FOV twice as wide as well.

With a focal length twice as long you would have a FOV half as wide.

Of course imager sizes don't vary any where near the degree focal lengths do, which makes focal length more of a practical determinant.

Login to read this IPVM report.
Why do I need to log in?
IPVM conducts unique testing and research funded by member's payments enabling us to offer the most independent, accurate and in-depth information.

Related Reports

Backboxes for Video Surveillance Tutorial on Aug 15, 2018
Backboxes are a necessity in surveillance, whether for managing cable whips, recessing cameras, adding wireless radios. But it can be confusing to...
Camera Focusing Tutorial on Aug 09, 2018
A camera's focus is fundamental to quality imaging. Mistakes can cause important problems. In this guide, we explain focus issues and proper...
Hikvision PanoVu Mini Tested (Multi-imager + PTZ For ~$500) on Aug 07, 2018
Hikvision has released their first PanoVu Mini multi imager, the PanoVu DS-2PT3326IZ-DE3, with four 1080p imagers, including a PTZ and integrated...
Panasonic 9MP Panoramic Fisheye Tested (WV-X4571L) on Aug 02, 2018
Panasonic has released their latest fisheye camera, the WV-X4571L, with 12MP sensor and 9MP resolution, claiming "extreme image quality" under...
Installing Surveillance Cameras Into Synthetic Stucco (EIFS) Tutorial on Jul 30, 2018
Mounting cameras into synthetic stucco, commonly known as EIFS finishes, can be problematic If not properly planned, EIFS/stucco can be downright...
Door Swing Tutorial on Jul 24, 2018
The direction a door swings might seem minor, but it can greatly impact door hardware selection. There are four basic ways a door can swing, and...
Installing Dome Cameras Indoors Guide on Jul 16, 2018
IPVM is producing the definitive series on installing surveillance cameras. This entry covers one of the most common scenarios - installing dome...
Panoramic Fisheye Camera Shootout - Avigilon, Axis, Dahua, Hanwha, Hikvision, Oncam And Vivotek on Jun 27, 2018
IPVM tested Avigilon, Axis, Dahua, Hanwha, Hikvision, Oncam And Vivotek 12MP panoramic fisheye cameras head to head, as shown in the test setup...
Installation Hardware for Video Surveillance - Indoor Fasteners on Jun 22, 2018
As part of our Installation for Video Surveillance series, in this note, we cover drywall anchors. A key part of installing security hardware is...
Hikvision 12MP Fisheye Camera Tested (DS-2CD63C2F-IV) on Jun 14, 2018
Hikvision's DS-2CD63C2F-IV is their flagship panoramic camera, with a 12MP imager, 15m integrated IR, smart codec, and more. We tested the 63C2 in...

Most Recent Industry Reports

Chinese OEM Avycon Gets ADI Push on Aug 15, 2018
Who is Avycon? An American company? A Korean company? A couple of guys relabelling Chinese products? The latter is the best explanation. While...
Backboxes for Video Surveillance Tutorial on Aug 15, 2018
Backboxes are a necessity in surveillance, whether for managing cable whips, recessing cameras, adding wireless radios. But it can be confusing to...
Genetec Stratocast / Comcast 'Motion Insights' Examined on Aug 15, 2018
Comcast recently announced "SmartOffice Motion Insights", an extension to their Genetec OEMed cloud video service (covered by IPVM here). This...
SimpliSafe Violating California, Florida, and Texas Licensing Laws on Aug 14, 2018
IPVM has verified that DIY security system provider SimpliSafe, founded in 2006 and acquired in June of 2018 at a billion dollar valuation, is...
Ban of Dahua and Hikvision Is Now US Gov Law on Aug 13, 2018
The US President has signed the 2019 NDAA into law, banning the use of Dahua and Hikvision (and their OEMs) for the US government, for US...
Cut Milestone Licensing Costs 80% By Using Hikvision and Dahua NVRs (Tested) on Aug 13, 2018
Enterprise VMS licensing can be quite expensive, with $200 or more per channel common, meaning a 100 camera system can cost $20,000 in VMS...
Nortek Sues SDS, Battle Over Unpaid Bill and Cancelled Lines on Aug 13, 2018
Nortek and SDS legal battle continues. As IPVM reported, SDS sued Nortek alleging bribery and antitrust violation. However, Wave fired back at SDS,...
Uniview Intrusion Analytics and VMD Tested on Aug 13, 2018
IPVM's IP Camera Analytics Shootout featuring Avigilon, Axis, Bosch, Dahua, Hanwha, Hikvision created some ill will with a Uniview distributor who...
ADT Employees Protest ADT CEO on Aug 10, 2018
So many ADT employees were so upset with ADT's CEO speech reported on by IPVM, that ADT's CEO was forced to send a mass email to employees to...
Axis / Avigilon Legal Battle Rises on Aug 09, 2018
In what is shaping up to be high-powered, will-not-back-down battle, Axis and Avigilon are squaring off in multiple legal contests. In 2017, IPVM...

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