Seeking advice

[techen 0]

Hey fokes, I have my CCTV set up. Bought a cheap one off amazon however was quite impressed by it. Got 3 cams set up on it already and is connected to the internet so I can view it on my PC or mobile. Works really well, No issues and such.

 

Anyway, I have 3 cams set up as I said. Two main cams are "960ps" which do the job, I bought a 3rd cam "1080p" does well too but I quickly found on the DVR is like duel channel? As in, the 1080p is on channel 3 and if I plug anything below 1080p on channel 4 my DVR will not display it. It has to match the same res as channels 3 cam. Which is kinda annoying.

 

Anyway, For my 4th cam I want a pan/tilt one and I could only find one on amazon that was within my price range and had a BNC connection.

 

The only issue is they say its a 1200TVL and am not entirely sure what 1200TVL is, Am guessing its far from 1080p and wouldn't work with my current system. I can't find any 1080 pantilts with BNC

[GREGRUSH 0]

The definition of TVLs (or its full name: HTVLs) is: Horizontal Television Lines: the number of VERTICAL black and white lines that can be counted horizontally on a space equal to the height of the screen. Ok, to put it in layman terms: take a TV screen (aspect ration 4:3, that is 4 wide, 3 high) and put a picture in it that consists of vertical black and white lines. You can distinctly see the lines (not a gray pattern). Then measure the height of the screen and use that measurement to set the limit of the amount of lines you can count from left to right . You should end up with a perfect square full of black and white lines. COUNT them (horizontally). if you get 500. that is 500 TVLs.

That is how TVLs work and it applies to ANALOG cameras on what is called STANDARD RESOLUTION. The maximum amount of TVLs for NTSC (USA) is 704. for PAL (EUROPE) is 720.

 

There is also DVR resolution and it has to be good enough to handle what the camera puts out.

For Standard Resolution there is CIF, D1 and 960H

960H is the best one and it can handle cameras with 700 TVLs. it is also called WD1 (Wide D1) coz it is a system that gives you a "better picture" by taking the pixels generated on a D1 system and duplicating each one. It is also called by us the "Fat D1"

 

HD is High Definition, but still Analog (not IP). They can be 1080p or 720p.

 

The cameras work not on TVLs but on MP (Mega Pixels) the "p" in 1080p means PIXELS.

 

The DVR has to be compatible with the HD technology of the camera. There are several:

HD-SDI, HD-CVI, HD-TVI, HD-TUBO, etc.

 

There are also hybrid and tribrid DVRs. This means that they can work with various technologies: CIF/D1/960H (Standard Resolution), HD (such as HDCVI) and IP. In some cases, they have some channels dedicated to analog, some to HD and some to IP

 

1200TVL cameras... Im sure some clerk got busy making out some formulas converting TVLs to pixels or pixels to TVLs in order to market their cameras with a bigger number. These are just analog cameras. Probably D1 or 960H. NOT HD and NOT IP. Probably 600TVL.

 

It looks like you have some type of HD system (1080p with BNC connector), so this 1200TVL camera will NOT work with your system.

 

TVL cameras are soon fading away as they dont give good quality footage. These are installed by people that need a CCTV system just for legal requirement (not due to security concern). These days, most systems are either HD systems (HDSDI, HDCVI, HDTVI, etc.) or IP.

 

When you buy a PTZ (Pan-Tilt-Zoom) camera be sure it is with a resolution that your DVR can handle. Also, be sure your DVR has the control connection for it (RS485). Keep on looking, there are lots of PTZ cameras that are IP cameras, but there are also quite a few HD PTZ cameras out there!

 

Good luck with your system!

 

Gregory Rovira logging off!