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CCTV Cameras
There are literally thousands of CCTV cameras available in the marketplace,many prices,many brands,many specifications.It is important that you pick the best one to suit your property,lighting conditions etc.Do you need indoor or outdoor cameras,do you need day and night cameras,do you need hidden cameras,or covert as a deterent?
The main things to take into account are lighting and distance of subject.In a normal home or business,the lighting conditions vary widely,so you need a camera with a low Lux factor,below 0.5 lux,you will probably need an infra red camera (as above) where the infra red beams switch on automatically below 1.00 lux,this will allow the camera to see in very low light conditions.The infra red beams on the above camera perform up to 15 mtrs,others are less (cheaper),some cameras more than 15 metres (more expensive).
The above camera has 420 lines,for better pictures,some have more (more expensive) some have less (cheaper) the minimum specification for any camera should be 420 lines.
Be carefull to check these things before installation,how it looks can be important but performance should be the overiding concern.
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Digital Video Recorders have come a long way in the few years they have been in the marketplace,they seem to be changing on a monthly basis and are by far and away the most popular method of installing a digital CCTV system.As you can see from the above schematic,they now come loaded with many features that where not possible just a few years ago in this type of control unit,only in a PC based unit.IE :Triplex recording (you can operate most other functions whilst the unit is still recording),high capacity disc space,remote monitoring,in the example used above,which is a middle price range unit,you can even download onto a USB stick and replay on any windows PC.So these units are sold and installed in their thousands.From experience,we know that they are mostly reliable as we have installed many of them for customers too.
In the writers opinion,there are no great advantages in these type of units except; price,when installing a small 4 camera system and when installing for a customer who can not use a computer.The popularity of these units is not that they are better,more reliable systems than PC based systems but because,most installation companies do not have the experience or expertise to build a customer a PC based solution,so they offer their clients the easier option for them (the installer) of an off the shelf,mass manufactured,sealed unit.In most cases these units do a very good job.
The disadvantage of these units is as follows: The parts and operating system are inferior to a PC based system,some of these units are still using Windows 2000,they have smaller RAM etc and are therefore slower than PC based systems.They are,mass manufactured, sealed units which means in the case of breakdown they must be returned to the wholesaler for service,you will either be without a DVR (countless cases of this) or you must rely on the goodwill of your installer to replace it immediately,so they are harder to service.Another drawback, we have witnessed this countless times,is actually operating the system,it is not simple,neither do they follow a standard format as PC`s do,sometimes it takes months to master them,using them where you have multiple emloyees or family can be a nightmare.So operating the system is not as simple as a PC based system.Comparing similar price ranged system to a PC system,the picture quality is not as good because of the inferior operating system, RAM etc.,nor is the speed of picture recovery as good.Should power fail,upon recovery of power,these units have to be manually switched on,so you could lose hours of actual events, if no one is on site to attend the unit.
These units do allow for remote viewing (see above) but it is far more complicated to set up and to access remotely,all systems require remote viewing software and it may require monthly fees to properly set up your remote access,though the actual viewing,once set up correctly is fine,however it is the writers experience that very few of the users of DVR set up remote access.The latest of these units allow USB stick transportation,which is very simple but the majority require downloading via the built in DVD writer on to a disk,as the PC system does and then the viewing software installed by the Police etc.These units usually have a plug in for either a security analogue monitor or a PC monitor for higher resolution.Another drawback is that if your CCTV system grows,ie: you have an eight camera sytem and need three more cameras,you would have to purchase a complete new unit,you would then have two seperate systems operating,with all the susequent cost and user problems,with a PC based system,you just add an extra card (see PC page) and plug the cameras in,it is still only one system.A cheaper,more user friendly solution.
We are certainly not against the supply and fitting of DVR units indeed we have installed them for our customers too,this critique is just an honest attempt by the writer to lay out the differences,for you the user,so that you can make a more informed decision on what type of system to use,this is something,I believe,that is not pointed out to potential customers by the installation companies.Both types of systems are a fairly large investment and are obviously very important to the customers peace of mind,we believe,this information should be made available.
Another thing about the supply of DVR units (and all CCTV equipment),is that potential customers are rarely offered a tailored solution for their needs,this is because the installation companies use credit accounts with only one or two equipment wholesalers,what this means is that the wholesaler is in actual fact financing the installation company to,in some cases, tens of thousands of pounds per month.The installer is limited in what he supplies to you, usually it is limited to the equipment offered by their wholesaler,which may not be the best equipment for you.They buy from other wholesalers at their peril.We have trade accounts with many different wholesalers but not credit accounts and search the marketplace for the best solution.We might buy cable from one,cameras from another,specialist equipment from another,DVR or PC based system from others.Each application is tailored by specification for each installation.
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