How to choose a Surveillance CCTV Camera
When shopping for a security camera it is important to know what resolution means. CCTV surveillance cameras have a resolution range from 330 TV Lines (television lines) to 600 TVL. Now for color resolution, CCTV cameras max out at 560 lines, however you can get black and white CCTV surveillance cameras in 600 TVL. IP security cameras are now available in much higher resolution, up to 5 megapixels. So what does all this mean?
There are many choices of security cameras all across the web , it is fairly easy for a consumer to get overwhelmed in finding the best surveillance camera for their system needs. Before buying a new security camera or complete system, there are some basic things that all consumers should consider in order to make a good choice. Hopefully this will help guide a non-technical person that is researching the purchase of a security system. The topic of this article is security camera resolution.
Here in the USA, normal Television transmission (not high definition) displays 480 lines of resolution. So it is possible to buy a CCTV camera that can record equal to or greater resolution than TV. The higher the resolution of the camera that you choose, the more detail you will see when you play back the surveillance video. Now a High definition television (HDTV) displays either 1080 or 720 lines of resolution depending on the channel and the type of HDTV that you have. In order to get higher resolution from surveillance cameras, the "only" choice is IP based megapixel cameras, which is connected over an IP network instead of a closed circuit. In general, IP mega-pixel cameras are much more expensive than CCTV cameras. These are designed for high end applications that demand really high resolution, believe it or not a megapixel cameras can capture surveillance video at more than twice the resolution of high definition television.
Some people that are shopping for a security camera are unrealistic (because of their lack of experience) about what a surveillance camera can capture (especially CCTV cameras). I will go into more detail about lens types at a different time. I will explain it briefly as it is so closely related to resolution. For example, we will say a 3.6mm lens which gives you about a 90 degree field of view outward from the lens. Most consumers think that if you take a 480 lines of resolution camera with a 3.6mm lens that you will be able to get a clear picture both of an object that is 20 feet away and an object that is 80 feet away. This is not true. While the 3.6mm lens will easily pick up the object in detail at 20 feet away, it will not pick it up at 80 feet away. In order to pick up the object at the further distance, you have to either use a larger lens that would make the image appear more close up or use a high end megapixel camera that would allow the operator to zoom in digitally without distorting the picture. Digital zoom is possible with high end megapixel cameras, but not with normal resolution CCTV cameras. Because of the huge price difference between CCTV and IP mega-pixel cameras, a lot of times it makes sense to add additional CCTV cameras instead of upgrading to megapixel cameras. This will lead us into the next article which will be about understanding and choosing the right camera lens.
I would love to hear any thoughts on this article so please feel free to post comments and i will respond to any questions.