CCTV: Questions & Answers

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Welcome back! Do you have any questions?

Client

Hi, Just trying to get my head into the different options as this is the first time i’ve looked into the details of CCTV

I love the buyers guide by the way very helpful

I just wanted to check, the difference between HD-CVI, HD-SDI, and HD TVI is not in quality but just in standards that different makes choose to use?

JMC

basically yes – they are all capable of 720P or 1080P resolutions – so image quality through all three is very similar

Client

Which is recommended? I have read somewhere that HD-TVI is probably going to industry standard moving forward?

JMC

SDI is however a digital signal – has a few negatives – mainly to do with cables, have to be very good quality and can not do long runs (90M) or more without using repeaters which cost a lot

SDI is definately a dying technology

Client

Thats handy to know

JMC

TVI & CVI will both be around for a long time i believe – basically TVI is being promoted by hikvision (largest cctv manufacturer in world) CVI is developed and being promoted by Dahua (approx 3rd largest CCTV manufacturer in world)…

They wont use each others – so they will both be around for the long haul – be aware they are not intercompatible

Client

Ah… ok i see thanks. Wasn’t sure which is better. So you would recommend HikVision?

right ok ta

So that means that if I buy HikVision, I have to use HikVision cameras? Same with Dahua?

JMC

well, there are other brands that also have tvi or cvi cameras – for example we do sell our own brand of TVI cameras (iSentry) which are a good value alternative to hikvision…

Client

oh ok

JMC

but currentlt we only sell the dahua CVI cameras – mainly because we are focusing on high end cameras – if you look at CVI cameras, you will see they all have motorised zoom lens – a great feature – meaning you can zoom the camera in / out remotely from the DVR

Client

Ah right ok

I think our budget is about £600…

…I have been tasked with finding the right equipment for a large meeting hall…

…Looking a probably 6 cameras total…

…One or two outside and the rest to cover different areas internally…

…any rexcommendations?

JMC

a little over your budget would be something like: https://www.jmcsecure.co.uk/proddetail.asp?prod=iHDT622

a little under the budget (but not when you choose cables etc) would be https://www.jmcsecure.co.uk/proddetail.asp?prod=iHDT623

Client

I was looking at that one before. These are manual set cameras?

JMC

big difference between the above two systems – the more epensive has vari-focal (manual zoom) lenses

Client

Yeah, the second one is the one I really had my eye on

JMC

so you can adjust the angle of view – this is a manual adjustment when you are installing the equipment

Client

So that means that you cant adjust them on the console or over the web?

JMC

(the cheaper of the two systems has a fixed lens (appros 85 degree anfle of view))

manual adjust means directly on the camera itself, there is a zoom & focus screw on the camera – you manual adjust it

Client

yes ok

so whats the maximum and minimum view of the manuak zoom?

JMC

the widest angle would be approx 95 – down to a narrow angle of around 30 degrees

Client

ok

whats the lowest price for a system with motorised cams?

JMC

that would be these: https://www.jmcsecure.co.uk/cctv-systems.asp?scri=3,43

as you can see – well above your budget i’m afraid

Client

ohhhhh

JMC

also be aware the tvi & cvi products we sell all come with 2 year warranty – so gives you a little more peace of mind

Client

We need something that will alert us to any signs of intrusion and have a decent enough picture to identify intruders

yeah, thats a good point and worth all the money right there

to be honest, there isn’t much in the price

It’s just some come with extras like door alarms, motion sensors etc

JMC

ours is just the cctv i’m afraid we do not sell door alarms or sensors

Client

Am i right that some have the ability to sense movement and trigger an email or sms to designated person?

JMC

all our kits can do that

in the menu you can set up motion detection recording, or have it record 24hrs a day

in the CVI you can also have push notifications to your iphone / android

Client

So the sensor is built into the camera?

JMC

no, it uses pixels in the image to determine motion – so it is built into the recorder

Client

the iphone one is through sms or an app?

oh wow, thats clever

any advantages/disadvantages to physical motion detectors?

JMC

through an app

they say the motion sensors can cause less false alarms, cant be sure as we do not sell them

the DVRs you can adjust sensitivity and even block out certain areas (like trees etc)… but maybe not as good as a proper motion sensor

Client

You can reduce that buy using infrared lit cams though yes?

JMC

not so much – i dont think the infrared has any effect on the motion detection…

apart from at night of course

Client

thats helpful thanks

are there any motorised domes that detect motion and move to capture it?

probably e
xpensive thought

JMC

no, you would need motion sensors connected to the dvr to trigger an alarm and then set the camera to look at a certain area once that alarm is triggered

Client

oh ok, manual programming

JMC

nothing has all that built in, you would buy a camera with alarm inputs, and then motion detectors separately

yes – that would be a complicated set up – but most good installers can do it

Client

yeah ok, place them around the room and each one triggers the camera to look in its direction

think thats too much for us

We’ll just focus on static for now

One last question…

…in your experience, how much disk space would you recommend for a 6 camera setup?

JMC

1080P?

Client

yeah

JMC

roughly – 6 x 1080p cameras recording 24hrs per day @ 12.5 fps = 1000GB = 4 Days

the tvi systems are limited to 12.5fps @ 1080P

the cvi systems can do 1080P @ 25fps – so that would half the recording time

Client

i see, didnt know that so that handy to know

JMC

this is all adjustable in the menu, you can set frame rates for each camera

Client

oh now that an interesting difference between the two

yeah, can we get away with 12.5fps?

does it make much difference on quality?

JMC

i would say yes – realtime (25fps) is mainly used with fast moving objects i.e cars… just people, we usually recommend setting up at between 6 – 10fps

Client

Yeah, this will only really capture people movement. We want to make sure that a face is easily recognisable on video in case we to prosecute

JMC

thats all about camera location / lens etc

the vari=focals give you better options, as you can adjust… but your facial recognition cameras need to be at the entrance points – other cameras around the hall are “monitoring” cameras

if that makes sense

Client

So even lower quality has that potential when set up correctly

Yes, makes total sense. I do photography to I understand the difference a lens can make. Any camera recommended in our budget? Any of these on your site be fine?

JMC

these are all the 6 camera kits we sell: https://www.jmcsecure.co.uk/cctv-systems.asp?scri=3

theres only one or two within the budget – but once you add cables / choose bigger hard drive, you will be over the budget.

Client

Right i see

Thank you so much for all your advice…

I was looking for a decent CCTV site for a while on google and yours was by far the best

JMC

thanks – any questions do not hesitate to get in touch

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