Surveillance Camera Imager Tutorial

By IPVM Team, 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.

imager free image4

Sensor ** ******

******** ****** ************* **** these ********** '******' ** 'imager'. **** ********* ** surveillance *******, **** **** the **** *****, ******, technically, ** ****** ** a ******** **** ** sensor. ******* ** ****, we **** ********* ***** to '******' **** ******** about ************ *******.

CCD ** ****

*** *** **** ********** types ** ******* **** been *** *** ****.

*****, ** ****, ********* all ************ ******* *** CMOS, **** *** **** 'best' ** *** '*****'. This ** *** ******** of * ****** ***, when *** ******* **** predominant *** **** *** looked **** **** ** a ***** ****, ***** quality ***********.

******* *** **** *** better, * ********* ******* against ****. *******, **** is *****, ********** ***, as * ********* ******, impossible. ** *** **** choose *** *******, *** would ********* ****** *** modern ************ *******, ********* the '***' ****** *** models.

**** **** ***** *** still *** ******* **** in **** ********** ************, such ** *** ** machine ******, *** **** these ************ **** **** increased *** ** ****.

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

***** *** **** * few *********** ************* ** surveillance *******, **** *** most ********** ***** *******************, ****** *** ****. Like ****** *************, ****** manufacturers ***** * ***** of ****** **** ******* size, *** **********, ***** rate *** *** ************, to **** * ***.

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

****** ************* ***************** ****** ************ / models **** ***, ** it ** *** **** to ******* *** ******* based ** ***** *******. Some **** **** *** imager ************ *** *** the ******** *****. *** example, **** ** *** knew ** *** ************, ********** ***** ****** of ******* **** ******* price / *********** *********. Moreover, **** ** *** knew * ******* **** using *** ***** **** imager (***** ** ****, in ********), *********** ** tuning, ******** *** *********** could ***** ****** ** noticeable ******* ***********.

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

******* **** ** *** maximum ********** **** *******. This ********** *** ******'* overall **********. **** ******* max *** ** ***, 1.3MP, ***, ***, ***. Recently, ** / **** sensors **** ******* ***** is ******* ** ****** 4K *******.

Imager ****

******* *** ***** **** extremely ***** (*.*., *****) to ********* ***** (*.*., cell ******). ************ ****** imagers **** ** **** in *** ******, ******, but ********* ******, **** cell ***** *******.

*** ***** ***** ***** contrasting ****** ****. *** two ****** ******* ** the **** *** ****** are ******** *** ************, while *** *** ** the ***** (*/*.*") ** actually ***** ****** ***** for ******* ************ *******, but **** **** ******* to *******:

imager size comparison

** ************, **% ** cameras **** ******* **** are ******* */*" *** 1/4". *** **** ****** imager ***** ** *** models ** ************ */*.*", 1/2.7", *** */*". **********, lower ********** ****** (****/*.*** and *****) ***** **** smaller */*" *******, *** even ***** ****** ************* use ******* ****** ** 1/3" *****.

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

**** *** **** *** years, *** ******* ****** size *** ********* **********. As *********** ******** ** 4MP, ***, **, ***., imager ***** ****** **** 1/3" *** ********** ******** more ******.

Rise ** */*"+ *******

*** **** ********* ***** in ****** **** ** the **** ** */*" imagers ** *** **** few *****. **** ************* now **** ** ***** one "**** ***" ***** model ***** * ~*/*" (or */*.*", */*.*", ***.) sensor, ******** *** ***** low *****.

************, ****** ********** *-*** models ***** */*" ** slightly ****** ******* *** now ********** ******, ********* in *************' ****** *********** models, **** ******' ** ***** *** 5MP *****, **** */*.*",****** *** ***-*****(*/*.*"), *********** *** **-*********-****(*/*.*").

Much ****** **** */*" ***** ****

******* ****** **** **** larger **** */*" *** still **** **** ** surveillance, **** **** * handful ** *******.********'* ********* ** **** ***** for ***** *** ** large ******* (**.***/~*.**"), *** others **** **** ******** as ****, **** ******'* **** *****,**** *****(***-*, ~*"), **************'* ***** */* ******.

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

****** ****** ************, ****** size ** ****** ****** disclosed ** ****** ************* on ************* ******. **** is ** ******* ** the ***** ** ****** typically ********:

Pixel ****

******* **** ** *** size ** ***** ******, measured ** *******.

***** **** ** **** strongly ********** ** ****** size *** ****** ** pixels (*.*., **********). *** bigger *** ******, ********** else *****, *** ****** the ***** ****. *******, if *** *** **** pixels (*.*., ***** **** SD ** **) *** the ****** **** ***** the ****, *** ***** size *********.

****'* ** ******* **** an ****** ************* ******* imager ****, ********** *** pixel **** **** ** side:

**** ****** ****** ***** sizes *******, ********** **** equal, * ****** ***** can ******* **** *****, and ********* ******* ******** / ****** *** ***** images. *******, **** ***** factors ****** *** ***** performance ** ** ** not ****** / **** to ******** *** ****** is ****** **** ******* based ** ***** ****.

****, ***** **** ** almost ***** ********* ** camera *************, ** *** best *** *** ** is ******** ** ******* at *** ********** *** imager **** ** **** model.

4K ******* ********* ******* ***** ****

** ******* *** ************ common. ******** **** **** ~4x *** ****** ** 1080p ******* *** ** camera ******* *** ********* larger **** *****, ********* the ***** **** *** 4K ******* ** *******. This *** **** *** light ***********. ****, ** we ******* *******, ****** in ***** ********** **** hurt ** *******.

**** **** **** ** not ****** *** ****, notably ** ***** ***** imager ****** **** ** Canon ** ****'* **** models, ****' ***-* *****, etc., ***** *** ****** imager **** ********* ***** size ***************.

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

****** **** *** * modest ****** ** ***** of **** ****** *****. *** ******* *********** of *** ** **** length (*.*., ***, ****, 30mm, ***.).

*******, *** ****** *** imager, ********** **** *****, the ***** *** ***** of ****.

** *** ***** ****, imager ***** ** ************ do *** **** **** much, ** **** **** notably ********* ****** *****, the *** **** ******* moderately. *** *******:

larger imager size wider angle of view

** ****, ** ********* is *** * ***** concern, *** ** ***** being ***** **.

Imager ** ******

******* **** ******* ** do **** *********** ***** (i.e., *.***,*****, ***.). ******* *** certainly ****** ***** ******* by **** **** ******* but *** ****** ***** the ***** ************ ** the ** ******* / System ** **** (***) to ******* ****.

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

******* *** ** ****, the *********, *** **** flawed, ****** ** ******* is **** ****** ******* always ******* ****** *** light ***********. ****** ****** imagers ****, ***** *** other *** ******* **** typically *** **** *********, namely *** ***** ***** processing **** ** **** by *** ******* / CPU ** *** ******. IPVM *** ***** **** in ********* **** ** *** light *********** *****.

*******, *** ***** */*" 1080p ****************** *** *** ******** ********* ****** **** the *** */*" ***** cameras, ** ***** ****** typically ***** *** **** (or ******) ********** **** in */*" ****** ** larger */*" ******* **** better ***********, ********* ** overall ****** ***********. *** our ***** ******' */*" ***** ******,***** ********* */*" ******,********* ***********, ********** */*" ******* *** Camera*** ********.

************, ***** *** * number ** */*" ****** cameras ********* ******* ***** processing **** *** ***** poor ** *** *****. Also, * ****** ** 4K ******* **** */*" imagers ** ******, *** are ***** *** ** low ***** ******* *** pixel **** ** ****** small *** *** ******* tend ** **** *** processing ***** ** ******* such ***** ***********.

Quiz ********

**** *** * ******** quiz *** *** *** well *** **** *******.

Updated ****

**** **** *** ********** released ** **** *** was ******* ** **** and **** ** ******* developments ** */*" *** larger ******* ** **** as *********** ** ** 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"

Molecular Expressions Microscopy Primer: Digital Image Processing - Spatial Resolution - Interactive Tutorial

"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.

Read this IPVM report for free.

This article is part of IPVM's 6,594 reports, 889 tests and is only available to members. To get a one-time preview of our work, enter your work email to access the full article.

Already a member? Login here | Join now

Related Reports

Multi-Imagers Added to IPVM Camera Calculator on Jun 15, 2020
IPVM has added multi-imager cameras to the Camera Calculator, supporting this...
Favorite Video Surveillance Hard Drive Manufacturer 2020 on Aug 27, 2020
Western Digital and Seagate effectively have a duopoly in hard drives but...
Uniview Deep Learning Camera Tested on Jul 14, 2020
Uniview's intrusion analytics have performed poorly in our shootouts. Now,...
The Future of Metalens For Video Surveillance Cameras - MIT / UMass / Immervision on Sep 25, 2020
Panoramic cameras using 'fisheye' lens have become commonplace in video...
Single Frame Gait Recognition From Michigan State and Osaka University Examined on Oct 01, 2020
Gait recognition has the potential for accurate identification at a distance,...
Quantum Dots Potential for Surveillance Cameras Explained on Sep 08, 2020
Quantum dots are starting to be used in TVs for better images, but how will...
Camera Course Summer 2020 - Last Chance on Jul 18, 2020
This is your last chance to register for the Summer 2020 Camera Course. This...
K7 Wall Mounted IR Temp Gun Tested on Jun 26, 2020
The original K3 model was missing a number of important features but the...
SafeZone Tech Presents AI Gunfire Detection on Jun 15, 2020
Safe Zone presented its AI gunfire sensor the May 2020 IPVM Startups...
Multilaser / Giga Security Brazil Company Profile on Oct 05, 2020
As part of our expanded Latin America coverage, IPVM is profiling regional...
Face Detection Shootout - Dahua, Hanwha, Hikvision, Uniview, Vivotek on Jul 30, 2020
Face detection analytics are available from a number of manufactures...
AndroVideo Presents Edge AI Face Recognition Cameras on Jun 26, 2020
AndroVideo presented its AI at the edge face recognition cameras at the May...
Hanwha AI Object Detection Tested on Sep 28, 2020
Hanwha has added detection and classification of people, cars, clothing...
Top Video Surveillance Service Call Problems 2020 on Oct 23, 2020
3 primary and 4 secondary issues stood out as causing the most problems when...
Augmented Reality (AR) Cameras From Hikvision and Dahua Examined on Oct 19, 2020
Hikvision, Dahua, and other China companies are marketing augmented reality...

Recent Reports

VICE Investigates Verkada's Harassing "RawVerkadawgz" on Oct 26, 2020
This month, IPVM investigated Verkada's sexism, discrimination, and cultural...
Six Flags' FDA Violating Outdoor Dahua Fever Cameras on Oct 26, 2020
As Six Flags scrambled to reopen parks amid plummeting revenues caused by the...
ISC Brasil Digital Experience 2020 Report on Oct 23, 2020
ISC Brasil 2020 rebranded itself to ISC Digital Experience and, like its...
Top Video Surveillance Service Call Problems 2020 on Oct 23, 2020
3 primary and 4 secondary issues stood out as causing the most problems when...
GDPR Impact On Temperature / Fever Screening Explained on Oct 22, 2020
What impact does GDPR have on temperature screening? Do you risk a GDPR fine...
Security And Safety Things (S&ST) Tested on Oct 22, 2020
S&ST, a Bosch spinout, is spending tens of millions of dollars aiming to...
Nokia Fever Screening Claims To "Advance Fight Against COVID-19" on Oct 22, 2020
First IBM, then briefly Clorox, and now Nokia becomes the latest Fortune 500...
Deceptive Meridian Temperature Tablets Endanger Public Safety on Oct 21, 2020
IPVM's testing of and investigation into Meridian Kiosk's temperature...
Honeywell 30 Series and Vivotek NVRs Tested on Oct 21, 2020
The NDAA ban has driven many users to look for low-cost NVRs not made by...
Ubiquiti Access Control Tested on Oct 21, 2020
Ubiquiti has become one of the most widely used wireless and switch providers...
Avigilon Aggressive Trade-In Program Takes Aim At Competitors on Oct 20, 2020
Avigilon has launched one of the most aggressive trade-in programs the video...
Mexico Video Surveillance Market Overview 2020 on Oct 20, 2020
Despite being neighbors, there are key differences between the U.S. and...
Dahua Revenue Grows But Profits Down, Cause Unclear on Oct 20, 2020
While Dahua's overall revenue was up more than 12% in Q3 2020, a significant...
Illegal Hikvision Fever Screening Touted In Australia, Government Investigating, Temperature References Deleted on Oct 20, 2020
The Australian government told IPVM that they are investigating a Hikvision...
Panasonic Presents i-PRO Cameras and Video Analytics on Oct 19, 2020
Panasonic i-PRO presented its X-Series cameras and AI video analytics at the...