Up until recent times the choice of CCTV System situation was relatively simple; Low budget = (outdated) DVR based Analogue CCTV versus higher budget = HD IP CCTV. It was still relatively simple to outline the principal advantages and operational key attributes of either solution.
- Analogue CCTV > utilises Coaxial cabling > is recorded on Hard Drives on a DVR (Digital Video Recorder > limits the max resolution to 4CIF (similar to DVD Res.)
- HD IP CCTV > utilises standard Network Infrastructure and Cat V cabling > streams to IP NVRs > enables megapixel resolution
With the introduction of HD SDI CCTV Technology to the UK security market, the clear borders of obvious distinction have somewhat blurred. Before we delve into technical depths, let us outline the basic structure as with the alternative technologies above:
- HD SDI CCTV > utilises Coaxial cabling > records to HD SDI DVRs > enables Full HD and beyond (typically 3 MP) resolution
HD SDI Installation Cost Comparison
Typically and generally quotations received for the installation of analogue systems should be the most affordable > followed by HD SDI in the middle ground > followed by HD IP CCTV. It is the author's opinion that IP CCTV is the best ROI option for most applications unless the project is an upgrade from analogue, providing an existing coaxial cabling structure and camera positions are not going to be altered much.
Customer orientated or industrial self-serving?
Naturally product solutions develop based on existing market demands. To really understand the current success of HD SDI it is imperative to ask the question - who's demand generates the market opportunity and why - is it the mostly CCTV un-informed customer, or is it the CCTV Integration Companies? Quiet naturally it is the integrator who advises the customer and has a high degree of influence on the choice of solution.
The industry situation really is that the long overdue migration from out-dated analogue to High Definition CCTV has been delayed by the integration force itself. The great majority of general Security Companies for which CCTV Integration is only one of many provided services, did not have the resources or motivation to completely start all over, training their engineers in IP CCTV, which is fundamentally different actually extending into the IT Sector. It is really this almost 'fear of the unknown and hesitation to progress into new fields' that creates the market potential. This is further evidenced by the general advertising slogans like 'Keep using Coaxial cable' - 'Stick with the components you know' etc.., which are clearly targeting the integration industry and not the end user.
It is certainly a good thing that HD SDI CCTV is now supporting the migration to HD by providing a solution to one of the greatest migration obstacles - but what has this all really to do with the customer and this being the best solution for him? In short - Nothing!
Our advice to the customer? Generally we only recommend HD SDI for small systems of up to four cameras or for projects that provide existing coaxial cabling structure. IP CCTV is the state of the art on all levels of involved technologies and has a multitude of advantages that will benefit the buyer and not the installer. A safe way of obtaining an integration-bias-free quotation is to request it from companies that have a good track record of IP CCTV installation references. This will ensure that you will not only be lead to HD SDI because it is the only solution they 'can' integrate.
A few interesting HD SDI (HD CCTV) questions for security integrators and potential clinets alike:
- Why is it an advantage for the buyer to be able to use coaxial cable (unless it is already in place)?
- Why would one possibly instal a (coax) cable that can carry only one (!) camera signal, when state of the art data cabling and networks can transmit many multiples of ten Megapixel CCTV Cameras per cable and are further overall less expensive, easier to maintain and actually 'already in place' far more frequently than 'old' coaxial cabling?
- What is also the great advantage of sending 3 Megapixel Video-Streams down a coax cable uncompressed. Surely the greater part of IT specialists would confirm that data compression has been a break-through in the communication and storage of data and most certainly not a disadvantage
- This one is interesting - What would we have to call a HD SDI Camera if the manufacturers were to add data compression and simply replaced the sophisticated coax utilisation interface with a standard network port? Our guess would be 'Megapixel IP Camera'?
Does answering all the above not lead us to the conclusion that it is all to the integrators' advantage, allowing him to further use coaxial cable instead of having to move on to 'that complicated network field'? Having said all that - HD SDI works (!) and there is nothing wrong with it. It satisfies manufacturer, distributor, integrator and client alike. We just though the client has a right to complete information prior to making a choice.
Watch this space - Coming soon: HD SDI vs IP CCTV - Comparison of advantages and disadvantages!