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Technology is advancing in leaps and bounds, Remembering the days when tube cameras were competing against the early CCD cameras. The sales pitch highlighted how little maintenance the CCD camera required, how they don't have problems with tube burn. How smaller the package were; and in all other aspects how comparable to the Tube camera they were. With these merits it was so easy to sell and hence the demise of the tube camera. Then came the poor technician who found big white blotches on screen that looked like a bright light burnt the CCD. How is this so? They said that the"CCD doesn't burn". Its only a new camera it can't be burnt. By accident he found as he sprayed a can of air to clean any dust on the CCD chip, a residue drop of moisture had magnified heat from the sunlight to burn some pixels. So now he learns you can burn CCD with extreme heat.

Then there was the technician who had setup the new replacement CCD cameras , only to hear the customer complain that the new cameras were not as sensitive as the old tube cameras he just replaced. So faster new lenses were being installed to help let more light in to compensate where higher sensitivity was required. As the lenses got smaller requiring less glass than their predecessor . They also got cheaper, the lens Replacement were feasible and sensitivity was not so much an issue. As the volumes were sold the packages were smaller the camera got cheaper to produce. The problems were better understood. The reality was smaller sizes lower prices and improved features.

Again and again new technologies push their way in, maybe slightly before time. With their acceptance follows promise to stand up to expectation. As with the CCD camera it may have seemed a bit gimmicky to have smaller cameras Now the board camera and even the chip camera is a reality. Because of this technology even manufacturing benefits. The new technology adds significance to the next. Each technology helps in the development of the next. Like the camera I saw with the ability for 8000 frames a second. You say what for, what a gimmick, you only need 24 frames a sec to get that illusion of motion. Well that was my first response, then I saw in slow motion as the frames were played back how it took forever to playback, a recording of part of a manufacturing process then it dawned on me , with such detail in playback it was possible to see a flaw in the process . Such high speed cameras can be thought of as an oscilloscope for mechanical motion, trying to analyze a high speed event. Without one is similar to designing and debugging a complex electronic circuit without an oscilloscope. Now that the analysis of a manufacturing process can be reviewed with such detail , the process of manufacture is assisted by an equipment at 1st thought to be a gimmick . It is now a tool in the manufacturing process. Chicken or the egg you think , well thats how amazing the leaps and bounds of technologies are moving. No sooner do we develop something and even before all the flaws are ironed out, that it becomes part of a system and you can't tell how it was being done before without it.

As we admire the human body and we try to emulate and reproduce its functions. The camera is just like an eye, with no way the perfection the human eye has. Even with such complex designs we keep developing more features all in the persual of reproducing human nature. So with every new technology it needs to be accepted and nurtured . I know I've been known to be critical in the past . This can be healthy remember the CCD camera that doesn' t burn. Well with healthy criticism at least we learn of what new heights we can reach and what limits there are at getting there. Today you just expose your problem or your objective and its only time and money between having a problem and having it resolved.

Go to the moon; why?, space travel ; what for? well as we explore these questions we raise others and resolve some more. Today it may seem unnecessary to have a camera surveilling the streets. Tomorrow it may be on a recording as evidence of a crime scene. Why not just have humans there , how many humans and how many is there?. We will always find resistance as someone feels threatened. Maybe their job is on the line or maybe their jobs worth is questioned. but normally their role only changes. So what next, maybe the parking camera? What for we can park with out them now! Well as the cities are overcrowded and the parking spots become smaller than a tin can then maybe the parking camera will not only be used in big trucks but also the average family car. It may double as a security camera with pictures being relayed via satellite of the culprit stealing the car. Maybe we will soon have someone develop the roving multiplexed view camera. Instead of multiplexing signals from different cameras all onto one recorder we will see the need to multiplex different views from the same camera. Or Maybe we will have such high definition cameras and scanning that we can utilise massive electronic zoom reducing costs by reducing the number of camera installations. Imagine one camera massive resolutions with massive digital zooms, 360 degree lenses and one digital recorder with massive resolution storage bandwidth. It may sound silly today but how will we accept it tomorrow.

Design  more than a security installation. .......................27/9/04

When designing Security  many considerations must be applied not only Establish Context, SWAT anlyses (Strength,Weakness,Oportunities and Threats) Risk Management practice, CPTED principles (Crime Prevention Through Environment Desisign)  ,   State and Federal Laws and Statutes,  Statistics, OH&S, and relating Standards such as AS/NZ or ISO.  One Other consideration that is often left to after implementation is that of  procedures and maintenance. When Placing these consideration high on the priority list , ongoing costs such how do we get our video from a DVR , how do we ensure it is backed up, should we install a camera so hard to get to that specialist equipment is required (cherrypicker etc) is  access to the equipment available during peak periods, what are the maintenance costs. All these consideration may sway decisions. when comparing the alternatives over the life expectancy or half life (time of major upgrade) of the system it  then only will the best decisions be made and  with a just  decision made ongoing acceptance and support of the system should follow.

DVR the latest wirlwind  in  CCTV security .................12/3/03

Digital Video Recordings are now a very popular product in the security industry. But look careful and like all products don't select your product on just price or reported specs. Check the ability of your provider to support the equipment and the features actually available at the time of sale and not the features in future revisions is what you should look out for. Be prepared to pay for good advice allocate a shootout and a report by a experienced consultant, highlighting the strengths and weaknesses and points of issue  particular to your installation. A day or 2 invested early and later at time of commissioning will ensure the installer provides you with the best unit and ensure it is setup correctly for your site. Make sure setup takes into account your priorities. These priorities should be documented and understood if at any stage they may require to be changed. e.g  building exit is setup for higher resolution and frame rate recording. this may change as this exit is shutoff and building changes are made. KNOW YOUR SYSTEMS WEAKNESS DON'T REST ON ITS STRENGTHS. Ensure sufficient harddrive is allocated and it is understood the expected time before data is over written and what  backup procedures are to be implemented.

What to look out for when getting quotes ................................12/10/01

Camera Specifications for sensitivity maybe quoted as 0.5 lux @ F1.4 Typically all sensitivity checks should be carried out at a known lighting level ( the light is measured on the subject or as reflected on the camera pickup device "the CCD") if lighting is measured on the object it should be known what reflectance the object has e.g a chart with a calculated 89.5% reflectance will reflect 89.5% of light upon it. so 0.5 lux is the light level that it can still get a acceptable picture from, when using a lens with an Fstop of F1.4 ( Fstop can be considered a factor of losses of the light through the lens glass or plastic whatever may be the case due to factors such as the opening of the lens that lets light through).

If a supplier left off the reflectance associated with the cameras specs and if its specs were based on 100% reflectance. It could be said that as objects do not reflect 100% of light upon them unless they are gloss white then the sensitivity may be overstated. Also if the lens used is not known of what its Fstop is or a Fstop higher than that quoted in the camera specs is used then the sensitivity will be overstated.

Take the case of Dome cameras do the  specs reflect the actual lenses used, again this may be that you are not comparing apples with apples. best to have a shoot out or put your trust in someone with the experience to have experienced the the differences in products. CCTV industry has many newcomers and they can not have the wealth of instant experience.

Lens eye view ........Specs for clarity, specs for distraction.

As published in CCTV Focus issue 1 AUG/SEPT 99

Often I am approached and asked if I have seen a latest product , camera etc., the specs are quoted as "colour camera with sensitivity good down to 1.2 lux " and so on. Or I get asked what's the best camera now days. When you consider the years of experience, design, build, test & manufacture many products involve. Isn't it amazing that an item can be compared simply as that one is a few dollars cheaper than another. For instance the amazing camera specification I get given, " look at this; isn't that a great camera its colour 470 TV lines, 1.3 lux sensitivity , DSP , 1/3 " CCD camera and look at its size" . In years past I have had to put cameras and many equipment up against the specs. Often some where in the tests you get a glitch and say how do they get that. Its here where I begin to learn reality and to the average spectator the basis of my skepticism evolves.

I remember as a young tech trying to commission the installation of a Ground to Air Aviation Transmitter and the spec say it was to achieve a 50 db Signal to Noise. This wasn't being achieved the best figures were lucky to be 40db. The 1st response was, is this equipment faulty, lets check on the standby. No its the same result , has the test equipment been calibrated recently. Yes still has a current calibration certificate. Can we confirm the results using a different technique and equipment batch, Yes we can. Well then is this Model or batch of equipment faulty and operating under expectation.

Further tests to equivalent systems proved this was a typical result. Well then what? Here my 1st lessons to take specifications beyond a one figure result came. The 50 db S/N is only possible at a predefined Bandwidth and therefore I was to filter out all other frequencies. In simple the analogy, if put to your vehicle was that your engine noise from the exhaust can not be more than the average voice ( for the sake of of simplicity we won't ask what is the average voice). To test this the exhaust would have to be taken away from the engine by means such as extending the exhaust through a sound insulated wall. Eliminating all other noises except the exhaust. Then here you could compare to the specification not louder than the average voice.

As you can see with every statement or specification many questions and clarification may be implied. Sometimes the conditions of the specifications are not obvious to the purchaser. So in making any very large investment. Consider your immediate budget and your projected budgets. Read the specifications with all the implications. Find out the conditions of specs and do they vary between product. Put it to a physical test under the same operating conditions & understanding the operating conditions, will assist you in achieving the best value for your money.

On larger projects / investment you may need to use a qualified person capable of putting to the test and comparing your alternatives.

When comparing cameras , do they compare with the same lens same conditions. Are the test conditions typical or useful to your conditions In My experience I have found that the difference in lenses demonstrate different qualities in a camera. Having spent much time in the past looking for poor contrast in a camera that otherwise performed admirably with sensitivity in darkness that put my eyes to shame. I found that the lens was the contributing factor to giving poor contrast pictures, due to the sensitivity of the camera other factors had to be considered . Such as Light reflections and refraction in the lens which normally would be considered insignificant, but in this case causing effect now contributing to a problem for a camera sensitive enough for this to be a problem. Or due to the sensitivity of the camera iris leaves were mainly shut in good lighting and such leaf design was affecting the distortion results. Now as camera packages become more and more a package with little options to the user , it is more critical that the cameras are put on site under real test and comparison. Comparison tests should all be based around your specific needs. When it comes to budget don't just look at the initial buy price consider ease of support installation. Will you get the next service personnel say to you its best you replace this part as its not economical to repair. In other words this could mean if you picked the typical system ( or this could even be if you selected a strong technical support team) then it could be maintained easier & more cost effective. Does your company want to invest in future technologies at all costs , or within reasonable ranges to other comparable systems.

As you can see Product selection is more than how cheap can I buy it, what one spec figure is, or does it have DSP (Digital Signal Processing).