Security cameras – it’s all in the technology

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Security cameras – it’s all in the technology

Selecting the right camera for security applications is far more complicated than what one would think. It is not just selecting the right camera; lens technology and image processing technology are also factors to be considered, as well as whether quality pictures are possible in low light conditions; or whether the image processing technology can handle an image with both bright sunlight and heavy shadows.
 
Apart from the fact that it's above all about price, the article is a bit of an amateur attempt to cover the issues.

Another important aspect when selecting a camera is the angle it will cover. If a camera is mounted in the corner of a room, will it cover the whole room and will the entire image be in full focus? There are cameras today that can do that.
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Well, duh. Except that most of the time your options are limited to picking your lens' focal length. Fancy corner cameras are normally lacking some or other essential feature you need.

Steyn also pointed out an important feature: the remote positioning of the camera. Some of the less expensive cameras have to be set up by a technician and cannot be remotely positioned, angled or focused. These cameras require someone on top of the ladder to keep adjusting the camera with someone looking at the screen and giving instructions. A remote positioning and focus control facility is almost indispensable, enabling one person to position the camera and adjust the focus from a PC, integrated into a security system or remotely from a tablet or smartphone.
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Eh, no. You get up on the ladder and set the camera. Once it's set, you don't touch it. There's no point paying ten grand extra per camera for bull**** features you're only gonna use once.

In some applications is it may necessary to be able to read number plates. A prerequisite is a good camera with ample telephoto or zoom abilities and the right software for the purpose.
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Telephoto, yes. Zoom, absolutely not. What does this oke think? The operator is going to control the PTZ and focus live?

What it comes down to is price. A good camera is gonna set you back R10k, and your NAS space another R10k. A small site will need several and a big site may need dozens. If you're not fitting these, there are other options, but you're always going to be compromising. Rather fit a few good 1.3MP cameras in strategic locations, than do nothing because the full 20 camera, 3MP, HDR, aspherical lens, PTZ system was quoted at R 500k. The article doesn't cover this very real problem.

Beri said:
it is all about TVL. Above 600 is ok
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The '90s called. They want their tech back.
 
iaywtimnbe said:
o_O
What on earth are you on about?
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If you don't know the difference between a tele lens and a zoom lens, best you stay far away from cameras. The TVL comment refers to the fact that you really, really, really shouldn't be installing analogue cameras these days.
 
Drunkard #1 said:
If you don't know the difference between a tele lens and a zoom lens, best you stay far away from cameras. The TVL comment refers to the fact that you really, really, really shouldn't be installing analogue cameras these days.
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And why might that be if it is for a home system ? and that is what is affordable ?
 
Drunkard #1 said:
If you don't know the difference between a tele lens and a zoom lens, best you stay far away from cameras. The TVL comment refers to the fact that you really, really, really shouldn't be installing analogue cameras these days.
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What are the sales figures for digital vs analogue cameras today? Are you telling the majority of suppliers and distributors that they're wrong?
There are many, many, many applications for analogue cameras today. Just as there are applications for petrol vehicles (invented in the 1800s).
 
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FNfal said:
And why might that be if it is for a home system ? and that is what is affordable ?
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You get what you pay for. If you're looking for a false sense of security, go for it, but don't whine when your recordings are 240x160 5fps, and you can't identify a licence plate or trespasser at 3m.

iaywtimnbe said:
What are the sales figures for digital vs analogue cameras today? Are you telling the majority of suppliers and distributors that they're wrong?
There are many, many, many applications for analogue cameras today. Just as there are applications for petrol vehicles (invented in the 1800s).
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Yes, I'm telling you that they're wrong. If they're selling analogue cameras into professional installations, they're wrong, and they putting their customers at risk. It's not about how old the technology is, it's about meeting the specifications of a well designed system.

Analogue:

4 cameras 600TVL, no HDR R 2 400
4 channel D1 30fps per channel video server or DVR R 15 000
8TB storage in a server R 8 000

Total R25 400

Digital:

4 Cameras 1.3MP, with HDR R 10 000
8TB storage in a server R 8 000

Total R 18 000

Not to mention that the digital system will record legible number plates at twice the distance of the analogue system.

Unless you're talking about Makro's R 4 000 camera kit running at 420TVL, recording at QCIF at 5fps?

As for petrol vehicles, I run a few old vehicles. A 15 year old vehicle is getting too costly to run regularly, never mind a 120 year old vehicle. Yes it's the same fuel, but modern, efficient cars are essential for professional users.
 
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Many budget CCTV cameras advertise "30m IR LEDs" which sounds like there are LEDs in the camera which will illuminate the coverage area up to 30 metres away. Many of them have over-optimistic resolution claims

This is not the case, they need some ambient light to help with the night-time image. In total darkness, as you will get on a farm, away from street lighting, they are useless. You will see the occasional ghostly image, but insufficient detail

Proper 0 lux cameras are just that. With 0 lux sensitivity and 20m LEDs, a person moving into the field of view will be recognisable

All you have to do is figure out the angle of coverage you need, bearing in mind that an ultra wide-angle lens will make everything look small so you have to tailor the lens to the application. If you capture an image and want to use this in court, as well as being time and date-stamped, it must be an unambiguous image of the subject

Number-plate recognition cameras, used by many neighborhood watches have the advantage of street lighting and any camera with a resolution of 800 TV lines will be able to used, plus the correct software.

In the end, you get what you pay for. The CCTV supply market is very competitive and prices are generally stationary while specifications steadily improve
 
Drunkard #1 said:
You get what you pay for. If you're looking for a false sense of security, go for it, but don't whine when your recordings are 240x160 5fps, and you can't identify a licence plate or trespasser at 3m.
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You seem to be a bit out of date with your analogue cams .

I have a system at home that runs 650 TVL cams , and a stand alone DVR .
The DVR records in 960H 25 frames per second on each channel , eight of them .
All the cams have sony 811 or 673 CCD sensors with 4140 or higher DSPs .
The system is more than adequate with one PTZ with a 673 CCD .
The whole system cost about 10 grand which is about the price of 2 decent IP cams.
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FNfal said:
Drunkard #1 said:
You get what you pay for. If you're looking for a false sense of security, go for it, but don't whine when your recordings are 240x160 5fps, and you can't identify a licence plate or trespasser at 3m.
Snip



You seem to be a bit out of date with your analogue cams .

I have a system at home that runs 650 TVL cams , and a stand alone DVR .
The DVR records in 960H 25 frames per second on each channel , eight of them .
All the cams have sony 811 or 673 CCD sensors with 4140 or higher DSPs .
The system is more than adequate with one PTZ with a 673 CCD .
The whole system cost about 10 grand which is about the price of 2 decent IP cams.
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I want to see that DVR's spec sheet before I believe it. Spec sheets for analogue DVRs are "generous" - D1 @ 1Mbps is no better than QCIF @ 1Mbps, and you won't find that info on many spec sheets. And again, we're looking at low end systems - Low res, non-HDR cameras and a DVR with questionable image quality and very little storage. Compare apples with apples. That system will barely compete with "plugging a few webcams into a MicroServer". At what distance can you identify an unknown person? At what distance can you read a licence plate? What are these figures in the dark?

I doubt you'll get any sort of competitive system at that price.
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You seem to be a bit out of date with your analogue cams , like i said before .
If you read the specs on the sony chips mentioned before you will see what they are capable of .
As for the DVRs i agree with what you said that is why when buying a DVR always over spec by 100 %
that way you will end up with a decent system .
The DVR systen has a 2 TB HD with the option to fit another 2 TB .
 
FNfal said:
You seem to be a bit out of date with your analogue cams , like i said before .
If you read the specs on the sony chips mentioned before you will see what they are capable of .
As for the DVRs i agree with what you said that is why when buying a DVR always over spec by 100 %
that way you will end up with a decent system .
The DVR systen has a 2 TB HD with the option to fit another 2 TB .
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OK, I'll admit that those new cameras are impressive (on paper). I've stopped looking at analogue because I'm not in that market. But a digital system is still competitive, and might have been a better option.

8 1.3MP cameras R 11 000
Microserver with 4 x 3TB (RAID 5 - 8TB usable) R 8 000

Total R 19 000

I just don't see the point of installing analogue when you can get the benefits of IP for just a few thousand more. Like I say, different markets. R 19 000 really is pocket change these days to anyone but some home-owners, and look at what you gain - 4 times the storage, RAID protection, and more than double the number of pixels per camera. In my market, if a camera can't identify someone at a specific distance, you install another camera, so more pixels means fewer cameras. And even with over speced DVRs, you're still not getting the pixel perfect image of IP.
 
If you are impressed with the 673 and 811 Sony chips, you should take a look at the new solutions using Sony IMX138 and IMX238 sensors.

These are quite a bit better and 115dB wdr models should be available in the country within a few weeks as well.
 
Having recently been though this we installed a huge system. Analogue. Was about 250k. Biggest mistake we made. Would have rather paid R450 and gone IP analogue is terrible compare to IP
 
mike156 said:
If you are impressed with the 673 and 811 Sony chips, you should take a look at the new solutions using Sony IMX138 and IMX238 sensors.

These are quite a bit better and 115dB wdr models should be available in the country within a few weeks as well.
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how good are they at night? can you recommend any good models that will have those sensors in?
 
Keigo said:
Add price with PoE or Non-PoE switch would be great, as switch is a main component of a IP camera system.
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Having just bought an 8-port Ubiquiti PoE ToughSwitch for work, I can tell you they go for around R2.1k... will save that money in cabling and hassle.
 
elvis_presley said:
Having just bought an 8-port Ubiquiti PoE ToughSwitch for work, I can tell you they go for around R2.1k... will save that money in cabling and hassle.
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Thats what I want to point out, network switch is not cheap also, specially PoE ones. :)
 
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