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It depends on the project

Hi-Tech Security Solutions recently published an article titled ‘It is not IP or nothing’. Following publication, Niall Beazley, director of Vision Catcher, sent us this reply.

I would highlight some key elements very relevant to South African installations – probably worldwide. Remember we have power fluctuation (surges), lightning and unbalanced power distribution that means you need UPS, surge arrestors and correctly shielded cabling running sensible routings that avoid fluorescent lighting, 220 V electrical cabling, correct earthing, correct phases, and many more small items that a base level installer may not have even heard of. For example:

1. The biggest issue with legacy analogue solutions is the standard of cabling used and its deterioration over time, plus the failure of the 12 V power supplies that are often used to provide power to multiple cameras. If you do not have 1 V peak to peak at an exact 75 ohms your image sucks. How can you install SDI on top of an already poor quality installation? In most situations to guarantee image quality you may have to replace cables.

2. Time lag or latency. Very few small and medium enterprises require real-time viewing on a 24/7 basis. 99% of all installations are for the purpose of historical review as they cannot afford to employ the screen watchers required for 24/7 viewing. The old trick was to show the amazing quality of the image on a CCTV monitor as the deal closer and allow the client to only see recorded footage playback if there was an incident. The sad part was that the recorded image on tape was a very poor quality and at a poor frame rate.

At long last we are seeing recorded footage at the same quality as the live images. Note that when you record the HD-SDI image it must also be compressed for storage purposes. Is the messenger not shooting himself in the foot by not stating up front that dealing with a live image in a live control room will give immediate benefits? As stated previously 99% of those SMME installations will be for recorded video.

3. Only one standard. First of all we need to check from whom these cameras are supplied, their reliability and quality; plus why are the major manufacturers such as Sony, Panasonic, Bosch, Samsung, CS-Lilin, Honeywell, GE, Pelco, Avigilon, Arecont Vision and many more not producing and driving the SDI range? IPVM has been discussing the issue in quite a number of articles and its commentary highlights HDcctv/HD SDI incompatibility and interoperability concerns.

4. The HDcctv Alliance itself sees this as a growing concern. In an August 2011 presentation in Beijing, the alliance stresses the importance of using HDcctv certified products rather than HD SDI. Specifically, the alliance notes that V1.0 HDcctv is more than HD SDI and that V2.0 HDcctv is not guaranteed to work with HD SDI. The challenge is that, while manufacturers are experimenting with digital HD video over coax, many are implementing HD SDI products, rather than conforming to the HDcctv specification.

5. Where is this range of HD-SDI product that is revolutionising the market as the next best thing? Remember that you get manufacturers that use high quality CCD or CMOS chipsets and those that use lower quality chipsets. How do you know what you have got? You have a shootout and assess their performance in all lighting conditions. I have often been amused when a range of 2MP cameras (to compare against the SDI cameras) are compared together – there is a reason why one costs only R1500 and the other R3000.

6. The best video management systems each cover more than 3000 different camera models. That is quite a number. Plus certain suppliers will offer freeware for limited numbers. Even in the case of numbers going to, say 16 channels, you can find solutions at less than R500 per licence plus a PC for around R6000? If I went to 40 cameras I could place them on one NVR without limitation on data throughput and record all 40 at their correct megapixel settings; this could be at 20 MP or even 40 MP.

Remember that 16 x 2 MP (1980 x 1080p) equates to just over 32 MP on one HD-SDI DVR. If we understand our data throughputs for a certain PC/server we are talking of running more than 80 MP of camera pixel count on one NVR, compared to 3 x HD-SDI DVRs – I bet my NVR is cheaper with the same storage capabilities than the 3 x DVRs. I do not have pricing on a 16 channel HD-SDI, but would doubt if it was less than R14 000. I am open to comment on this.

In summary, if you compare apples with apples, then yes there is a place for the HD-SDI as there is still a place for traditional D1 or less analogue cameras. By the way, why are there still so many D1 IP cameras offered? Because if you want to see what comes through the door a D1 camera may be all you need from a resolution point of view. The reality is that if end-users are properly informed and know what they really want (give the camera a job description) this will determine the best route to go.

If you want to pay peanuts for your solution be prepared to have it installed by the monkey who can plug in the RG59 to an SDI camera and the other end into an SDI DVR. Then what happens when there is induction on the cable, the BNC came off in his hand (just put a little more foil around it and stick it back on), there is no signal coming through despite these shiny new cameras because the voltage is less than 11,5 V?

Unless you have a correctly regulated industry that is capable of telling you the difference between an analogue camera at D1, CIF or 4CIF, against an IP camera with the same resolution, versus an HD-SDI camera against megapixel cameras, then do not be surprised when your solution fails to produce the evidence in the court case that is the reason why you installed the system in the first place.

I have not even gone into the reality of camera number reduction through using a higher megapixel camera rating or hybrid systems that more than cover different arguments that people might use. The fact is that you cannot compare an analogue quote with an IP quote against an HD-SDI quote and say that one is better or cheaper than the other without laying down some parameters. I specified a large service station with an existing 32 cameras and 2 DVRs installation all recording rubbish. My quote for the installer was for 9 megapixel cameras, plus cabling and NVR. The price of my solution was half the price of the original installation.

How would I upgrade the service station? Rip everything out and put in new cabling and then let the owner choose what he wanted. The owner chose megapixel cameras because he had an image that could be used in court and his whole focus was on area coverage.

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