Infrared Illumination

The main challenge in designing a CCTV system is the ability of a camera to be as effective during nighttime as it is during the day. By incorporating infrared illumination this is made possible.

Infrared illumination is used to provide light over scenes that would otherwise be too dark for a camera to create an image. It is a compromise because the best results can only be obtained by providing sufficient white light but of course this is not always possible. In many cases using powerful floodlights would cause a considerable nuisance and could be dangerous where there is road traffic moving towards the lights. It is also difficult to cover a large area when a pan tilt camera is being used, in this case the illumination is only required where the camera is directed and infrared lights provide the answer.




Only natural light provides absolute illumination, although it is of course affected by clouds and shadows. All forms of artificial light suffer from the fact that as the distance increases from the light source so the luminance reduces. This is due to the inverse square law of illumination where the luminance falls to a quarter of its value if the distance is doubled.

The first component that light from a scene has to pass through is the lens. If this is wrong then everything after gets progressively worse. Apart from selecting the focal length for a particular scene, there is generally very little thought given to this prime element in the chain to get a picture from a scene to a monitor. There are several factors in lens selection that will affect the effectiveness of a system under infrared light. Often they will determine whether anything at all will be seen.

The emphasis in system design for low light conditions must be to assess the products carefully, ask questions and do not shy away from quality products for the sake of a few percent on the price.

So, how far can your light shine? The answer is, of course FOREVER.

But, how far can your CAMERA see?




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SELECTING THE RIGHT CAMERA FOR THE JOB

With so many cameras available, how do you determine the right camera for your application? Below are some guidelines I use to help when deciding which camera to choose. Below I will provide you with the questions you need to ask and have answered before you choose the appropriate cameras for the job.

-What is the goal or objective of each camera?
-What specifically is the camera looking at or for?
-Is this a fixed or PTZ (Pan,Tilt,Zoom) camera?
-What quality of image will be needed and why?
-Is this an indoor or outdoor environment?
-How will you be mounting the camera?
-Will Audio be required?
-Are Video Analytics desired?

What is the goal of each camera that you want to use?
When choosing a camera it is important to understand what the expectations are for each camera view and its location. Looking at a parking lot is entirely different than viewing an entry way. You should look at the scene being viewed and determine what details your system (and ultimately the user) will need to capture. Do you need facial shots at 20 meter? Do you need to see a license plate number clearly or is this general surveillance? Is the video going to be used for management purposes, to help with operations or is it strictly for security? The goals you have for each camera will determine: the field of view, the placement of the camera ,the type of camera the lens required

What is the Camera looking at / What do you want to see?
In each location the distance from the camera to the desired object or objects of interest and the width of the area is going to be a major factor on selecting the correct camera as well as the number of cameras required to cover the area.

Fixed or PTZ.
There are many schools of thought on this but what I always ask is: Will there be someone live viewing the camera or will it simply be recorded for viewing later? If you don’t have someone to live view the camera (and control the PTZ), it may be more beneficial to have multiple camera’s looking at a desired areas than having one camera panning left and right or up and down missing all the action. New megapixel technology allows the recording of high definition images which will allow you to zoom into the video after it has been recorded while preserving detail. For example, a parking lot that is 200’ wide and 100 deep could easily be covered by one of the newer 180-degree 8MP IP cameras for the same price as a PTZ and will record everything, never missing a detail in the desired area. In addition, in some situations several analog cameras might provide the best cost / performance trade off. Of course, if you have a live viewing situation, a PTZ camera provides a great degree of control and is a useful tool.

Quality of image.
While we often talk about the benefits of the newer megapixel technologies, there are still many specific applications in which standard IP and the older analog cameras still provide the needed coverage for the best price. It all comes down to how much detail you need, the area you need to cover, and which technology can accomplish the task at the best price. For example in a grocery store where the aisles are narrow, an analog or standard resolution camera is still probably the best and most affordable choice. Over the cash register however, you may need to be able to zoom in too see the customers face or if the casher scanned an item. While you could place several analog cameras over the registers, a single megapixel may be the better (and more cost effective) option.

Color vs Black & White
These day’s camera’s come in Color, Black & White and Day & Night. A Day & Night camera produces video in color by day and switches to black & white at night. This is because a color camera may need as much as ten times more light to perform than a black & white camera. A day & night camera is often used in outdoor installations since it is harder to add lighting, but can be beneficial indoors as well when little or no light is available. A form of lighting that has become very popular these days is infrared lighting because it provides light that the camera can see, but produces little (or no) visible light which is sometime important. What is important for you to know is that color cameras are actually designed to react more like the human eye meaning they are not very sensitive to infrared lighting. For this reason, if you are using infrared lighting you should choose either a black & white camera or a day/night camera because these cameras do allow infrared light to come through . Knowing the light level in each area of interest is very important when designing a camera system.

Light
It is the number one factor in producing a good image from each camera. When choosing a camera for each area, the available light as well as the sensitivity of the chosen camera will be major factor in the quality of your video. Once you know how much light you have available you can make other decisions such as if additional lighting or IR lighting is needed. When looking at data sheets, Lux is the measurement of the cameras light sensitivity. The lower the number the better the camera will perform in low light conditions. One thing to keep in mind when comparing cameras is to realize that Lux measurements are somewhat subjective and not typically tested against a standard.

Does the camera require a housing?
Many cameras today come self contained in a dome or bullet style housing which is great for most typical applications. Many applications however, require specific housings to prevent vandalism or to keep out excessive moisture, heat, harmful chemicals, dust , insects, etc… There are special housing and enclosures rated for these special environments and applications so it is important to know exactly what the cameras environment will be.

Mounting the Camera
While evaluating the environment for each camera, you need to determine how the camera will be mounted. Will the camera be mounted from a ceiling, a wall or a roof top parapet? In ceiling mount applications; is it a hard ceiling or ceiling tiles? Will the camera be recessed or surface mounted? Consider any other factors that may be involved and could require special hardware or tools. Also consider the structural integrity of the mounting surface and its ability to provide a stable mounting surface and more importantly stable video.

Audio
If audio is required, consider whether one-way or two-way audio is needed as each may have their own special requirements and may lead you to consider one camera over another. In fact, some network cameras allow microphones and speakers to be directly connected to the camera which means you can eliminate the need for separate wiring drops for audio. It will also be important that your client is aware and in compliance with all local and federal laws related to the capture of live audio.

Designs with Video Analytics
Video analytics can be very simple in concept, such as “Tell me when the lines at the register are too long”, but highly complex to deliver. Analytics are obviously very useful as they can help personnel get immediate feedback about situations in the business without having to sit there and view the video full-time. When delivering a video analytics solution, we need to be extremely clear about what the customers exact expectations and desires are for each situation. A client may say “I’d like to identify license plates” which could actually mean two completely different things. One person may want to simply capture an image of every license plate for immediate review, while another wants the license plate number to be extracted from the video and go into a data base that is searchable. There are many forms of video analytics from basic object, motion or threshold detection to in-depth video analytics like people or vehicle counting, loitering, object left behind, disappearing object, directional motion and others. Many of these analytics algorithms are still being defined (and refined) by the industry so having a full description and understanding by both parties (the dealer and the client) of the desired results will be needed.

If you follow this guide you should have all the information you need to get the right camera for the job. I hope this has been helpful.

A warranty
A warranty encompasses a period immediately following acceptance of an installed security system during which the contractor is responsible to ensure the system operates as required by the contract. Warranties normally include coverage of all parts (as stipulated by the supplier in accordance with the suppliers guarantee period from date of installation), labour and workmanship included in the initial installation.

An extended warranty
An extended warranty implies that the warranty period is established beyond the standard terms offered by the contractor. An extended warranty should also include all parts, labour and workmanship included in the initial installation.

Maintenance agreements
Maintenance agreements are contracts established exclusive of the initial implementation, and may be put in place with the original contractor, or any combination of other service organizations. The servicing companies may be inside or outside contractors, and be responsible for individual components or complete systems.

Extended maintenance
Extended maintenance has no unique meaning. It only implies that a long-term contract may apply. While warranties are typically inclusive of the entire initial installation, maintenance programs may be sectioned into limited service categories.

Preventive maintenance
Preventative maintenance is just like visiting the doctor for a check-up each month. Whether one is sick or not, the doctor is able to see changes in their systems, and direct them to a course of action that may prevent health failure. Preventive maintenance is that, plus a trip to the dentist. The security system is checked by a qualified technician who reviews the system programming, tests circuits for changes in resistance, checks and changes batteries and adjusts components as necessary. .While giving the system its check-up, a thorough cleaning is also in order — with camera housings, lenses, equipment cabinets, power supplies and other equipment getting the once-over to ensure quality operations.

Software maintenance
Software maintenance is the regularly scheduled update of software programs to eliminate any bugs found since the latest release, and to add any patches that make the software
function better or provide added features for ease of operation.

System maintenance
System maintenance is the response to a problem, identified by the end-user. It may be provided under a time and material agreement, a fixed-fee contract for parts and labour or a fixed fee for labour with added costs for parts.

Pentagon supplied a range of Bosch components that offer the highest levels of security for Pecanwood members and residents at all hours and in all weather conditions. The new Bosch CCTV system keeps a watchfull eye over approximately 124 hectares and provides indoor and outdoor surveilance around the perimeter and entry/exit points of the estate 24/7. A range of high performance Bosch cameras have been installed at strategic areas throughout the estate including mini domes, infrared bullet cameras, thermal static and PTZ cameras.

The Bosch "Metal Mickey" camera has full 360' continuous rotation and 320' tilt control that allow security personnel to zoom in on incidents quickly and effectively in even the most extreme weather conditions. Bosch infrared bullet cameras, mini domes and infrared Illuminators were installed to provide extreme CCTV night vision at Pecanwood. The Illuminators provide maximum camera performance at night, limit light pollution and deliver an image with even illumination across the camera's entire field of view. The new CCTV installation enables residents and menbers to walk freely within the grounds, relax in nature and ebjoy a range of recreational activities in a safe, secure natural environment.

Garth Briggs, CEO of Holbert Integrated Technologies, says, "The success of this project has been inter alia, a culmination of high design standards set on the part of the client with special reference to Johan Kruger and Theo Potgieter for their personal input. A great personal relationship with Pentagon, who supplied the product and specifically their product knowledge and backup advice and lastly the standards set by Holbert in respect to this meticulous installation, focusing on the final product which was to ensure that there is a state-of-the-art integrated security system that adds value to Pecanwood and all of it's stakeholders.
I must commend Bradley Bell, Regional Director (Gauteng) of Holbert Integrated Technologies, specifically on his relationship with Pentagon and the client in ensuring that the project was completed within budget and to the required design and installation standards."

For more information, contact Pentagon Distribution
www.pentagon.co.za
CPT Tel: (021) 700 8360
JHB Tel: (011) 312 0745

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The funds raised will go towards the upgrade of the Burns Unit, which has not been upgraded since the Hospital was built in 1956. Approximately 3500 children with burns are treated at the Burns Unit every year, of which 85% of the patients are younger than six and 98% are from disadvantaged communities.

The rest of the teddy bears will be distibuted to other wards by the Friends of the Children's Hospital Association.

The Red Cross War Memorial Children's Hospital is the only stand alone, specialist hospital dedicated entirely to children in southern Africa, managing more than 250 000 patient visits each year. These sick children come from all over South Africa, Africa and in rare instances the rest of the world.

100% of funds donated to the Trust go directly to the Hospital and not a single cent is spent on administrative costs.

Thank you once again and we look forward to your continued support.

Kind regards

Sandi Sher
Communication Co-ordinator: Marketing
The Children's Hospital Trust

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