HD-SDI vs IP

[dahomes555 0]

I've been reading a lot lately about HD-SDI being able to transmit full 1080P resolution video using existing RG59 coax cable, so long as the cameras and DVRs are HD-SDI. The demos that I've seen appear to be stellar in quality.

 

Having mainly installed NTSC DVRs that are limited to D1 resolution, I've been looking on how to break into the HD market. IP has seemed like the way to go, but there is just so much upkeep and configuring that goes on with IP. You also run into bandwidth issues where having a decent sized system (8-10+ cameras) will basically require it's own network, otherwise it will just kill the bandwidth for the rest of the building.

 

What are the pros and cons of HD-SDI, in comparison to IP? In my opinion, IP has always given more flexibility and higher quality images, but with lower reliability (network dependent) and more maintenance. If HD-SDI can offer the great image quality, with most of the flexibility (DVRS are basically network appliances these days), then why would I use IP over it?

 

Thanks

[NotoriousBRK 0]

IP camera system "issues" and worries of network saturation are greatly exaggerated.

 

HD-SDI is a novel concept. Most people that have tested it have found that it's not going to work with "just any" RG-59 cable, so be prepared to do lots of cable pulling and re-terminations.

 

Most of the demo videos I've seen are not at all realistic. The HD-SDI DVR's are going to compress the video before recording it, using h.264. The live stream might or might not look better when compared to some IP cameras and VMS systems. But you can't record an uncompressed 1080p video stream without having literally hundreds of terabytes of storage. So, the recorded video (eg: what the customer will actually end up dealing with 99% of the time) will look exactly the same as video from a quality IP camera.

[dahomes555 0]

 

Most of the demo videos I've seen are not at all realistic. The HD-SDI DVR's are going to compress the video before recording it, using h.264. The live stream might or might not look better when compared to some IP cameras and VMS systems. But you can't record an uncompressed 1080p video stream without having literally hundreds of terabytes of storage. So, the recorded video (eg: what the customer will actually end up dealing with 99% of the time) will look exactly the same as video from a quality IP camera.

 

Yeah, I'm sure you wouldn't ever be recording video in full 1080p, as it would consume HDD space very quickly. But if the compressed video looks as good as a quality IP recording, isn't the installation/setup/maintenance easier on a coax system than an NVR?

 

As far as network saturation goes, I've experienced it on the few large (15+ camera) IP systems that I've installed. The bandwidth started to drop off pretty substantially. One customer that we did 25 cameras for anticipated the bandwidth issues and actually installed a completely separate network just for the camera system. Maybe we're all doing something wrong?

 

Thanks for the reply.

[tomcctv 190]

As far as network saturation goes, I've experienced it on the few large (15+ camera) IP systems that I've installed. The bandwidth started to drop off pretty substantially.

 

 

 

dedicated network all the time is best.

 

HD-SDI DVR's i have seen working IP is better MP and cheaper. what installers seem to be concerned about with HD-SDI is not having to replace existing coax. ??? is labour not a big part of your profit ???

[Soundy 1]

As already noted, despite claims from proponents, HD-SDI (and its name-branded variants such as HDcctv) is turning out NOT to "just work" with "any existing coax" - from all real-world reports, good-quality cable and terminators are a must, especially if you want full 1080P. Once you have to re-run cable, there's little advantage to pulling new coax vs. new Cat5e or Cat6, especially as UTP is far more versatile in the long run.

 

Besides, you can use IP cameras over existing coax using Highwires or similar devices... and they're not nearly as picky about the cable quality. In fact, on one site where the DVR was downstairs from the main area with the cameras, and running new cable was nearly impossible, I just put a new switch upstairs for the cameras, then used a set of Highwires to feed them all downstairs via a single old coax run.

 

Like Brian says, the "issues" with IP are greatly exaggerated.

 

And consider that while current HD-SDI designs are limited to 2MP (1080P = 1920x1080, or approx. 2MP), IP cameras are already FAR beyond that - 3MP and 5MP cameras are common now; 2MP is entry-level stuff.

[NotoriousBRK 0]

But if the compressed video looks as good as a quality IP recording, isn't the installation/setup/maintenance easier on a coax system than an NVR?

 

As far as network saturation goes, I've experienced it on the few large (15+ camera) IP systems that I've installed. The bandwidth started to drop off pretty substantially. One customer that we did 25 cameras for anticipated the bandwidth issues and actually installed a completely separate network just for the camera system. Maybe we're all doing something wrong?

 

Thanks for the reply.

 

I don't think it's any easier, especially when you take into account some of the enhanced flexibility you get from an IP system... The ability to cheaply backhaul multiple cameras over a wireless link (pair of Ubiquti radios, $150), ability to cover extreme distances without video degradation (fiber), remotely adjust camera image parameters and so forth.

 

I feel like some people are looking at HD-SDI not for the topology, but more for an excuse to not have to learn IP in depth. IP networks are so ingrained in technology today that there is no way (IMO) to make a solid living going forward without being very IP/Ethernet proficient. Sure, if you're 5 years from retirement maybe you can scratch out the last few years without having to understand how a subnet mask really works. But if you're just getting into this, or have a lot of years left, your time is going to be better spent learning IP networking instead of wasting time on stuff like HD-SDI.

[fa chris 0]

The highwire stuff works great for using IP cameras over existing coax if retrofits are your focus. If it's good cable as mentioned above, depending on the price of the HD-SDI gear it might be your cheapest easiest route if the HD-SDI cam+DVR+Power Supply (if not reusing the old one) is priced better than highwire+IP camera+POE network switch+NVR+software. You'll have to get quotes and calculate both of them out for a comparison.

 

Pulling new, you'll be much more future proofed installing cat5e cable, and it'll be cheaper than pulling new coax & a power cable. You also can't beat the flexibility of building your own network on larger systems, pulling 10 cameras to the nearest IT closet with one home run versus home running 10 cameras to the basement, not only is it a lot less cable but it's a lot less labor. It also gets you away from needing proprietary DVR's. You can buy any server from anywhere or have the owners IT group provide one (and maintenance it)... you just need to worry about the software package you're going to install on it.

 

Assuming you're dealing with commercial customers, offloading the head end (a dell or HP server? whatever they want and have standardized on which meets the requirements for your NVR software) and network gear onto the IT departments budget instead of the security budget helps sell your project.

 

ability to cover extreme distances without video degradation (fiber), remotely adjust camera image parameters and so forth.

 

I've put hundreds of analog cameras on fiber.

 

American Fibertek, Comnet, IFS, etc. all make good fiber stuff geared towards cctv/access control/intercom/etc.

[NotoriousBRK 0]

 

ability to cover extreme distances without video degradation (fiber), remotely adjust camera image parameters and so forth.

 

I've put hundreds of analog cameras on fiber.

 

American Fibertek, Comnet, IFS, etc. all make good fiber stuff geared towards cctv/access control/intercom/etc.

 

Who is talking about analog cameras?

[fa chris 0]

 

ability to cover extreme distances without video degradation (fiber), remotely adjust camera image parameters and so forth.

 

I've put hundreds of analog cameras on fiber.

 

American Fibertek, Comnet, IFS, etc. all make good fiber stuff geared towards cctv/access control/intercom/etc.

 

Who is talking about analog cameras?

 

You stated it as an advantage IP cameras have, just saying its not.

[NotoriousBRK 0]

 

I've put hundreds of analog cameras on fiber.

 

American Fibertek, Comnet, IFS, etc. all make good fiber stuff geared towards cctv/access control/intercom/etc.

 

Who is talking about analog cameras?

 

You stated it as an advantage IP cameras have, just saying its not.

 

Go back and read slower this time. The discussion was about HD-SDI vs. IP cameras. I never mentioned analog cameras. I'm aware that analog cameras can be backhauled over fiber (though even then you have to watch for high frequency rolloff and image degradation with *some* fiber systems). However, HD-SDI currently cannot. So, if you need to go a very long distance AND want a higher-res image (eg:NOT D1), then you will have major problems implementing that with HD-SDI.

[fa chris 0]

When we're talking about replacing an analog camera with HD-SDI in order to gain a better image using existing cabling we're talking analog infrastructure. The HD-SDI signal should be transparent to the fiber, and there are fiber transmitter/receivers compatible with HD-SDI (though I'm not sure how long they've been on the market, there are multiple options marketed specifically for it).

 

How well does it work? Dunno, makes no sense to me to try using one when so many options are available with IP cams.