Types Of CCTV (Closed Circuit Television) Cameras and Definition
Throughout the early 2000’s consumers saw a surge of prebuilt CCTV type systems come to market. Most of these “Chinese made” CCTV in a box system were okay for the era, but recent technological advancements in CMOS, optics, and DSP technology have rendered many of the systems inadequate even for the most basic installation. It is important to note that what makes or breaks a good CCTV system is the selection of cameras given the particular room or area they will be monitoring. Many factors have to be taken into consideration when making the selection. Today Closed Circuit Television systems and cameras have become a lot more specialized. You can now buy cameras and systems specially tailored to specific applications depending on environment factors. These factors include ambient light, weather conditions and environment as well as the speed of objects the camera will be recording. The following are some basic options you have when selecting the best type of CCTV cameras for your system:
Spy Cameras as the name describes are a group of cameras employed and disguised while in operation. These cameras are normally tiny, while there are some that are of regular sizes housed in disguising everyday items such as teddy bears, smoke detectors, clocks and many other types of furnishings. Spy cams became increasingly popular due to their falling prices and advancement in technology and have also lead to better picture quality and even built-in DVR systems.
The acronym PTZ stands for (pan / tilt / zoom) these are CCTV cameras with remote directional and zoom control. PTZ cameras are best suited for situations where the user needs to actively track a person or object. PTZ CCTV cameras can also be programmed to detect faces or motion and automatically track it throughout the field of view and some of the better ones can also operate in security guard mode where the camera can automatically execute a sequence of precepts including panning, tilting, and zooming in order to scan a large area on its own.
Infrared CCTV cameras or thermographic CCTV cameras are specially designed to see in the dark. Instead of the 450 – 750-nanometer range of the visible light camera, infrared cameras operate in wavelengths up to 14,000 nm. All cameras specified for this use can also be used for daylight surveillance; this is achieved by switching modes not by being full-spectrum capable. Unlike infrared cameras used by the military, most CCTV infrared cameras rely on infrared LEDs to shine on an area allowing the camera’s CMOS element to paint and image based on the level of IR absorption of each element in the view area.
As their name describes Dome cameras are cameras housed in a dome-like housing. This type of housing offers many advantages. For one, the camera itself is an exceptional level of protection and security from tampering and impact. The dome, which is usually tinted, can cast doubts on perpetrators since it is difficult to see if the camera is looking at you or not. Dome camera housings can also house several cameras in a single housing making it possible to cover the 360° area from one location. When used outdoors, dome cameras offer the best protection against the weather, especially snow and rain; they are also best suited and desired for areas with a lot of dust. The dome shaped glass seems to stay cleaner than those found in square housings.
Just like indoor CCTV cameras, outdoor cameras come in a whole range of shapes and sizes. The primary spec that one must take into consideration when selecting an outdoor camera is its capability to survive the weather. This is an area where many cheap CCTV outdoor cameras fall short. Whether you live in New York or Florida an outdoor camera is likely to be exposed to a wide range of temperatures and weather conditions. The second most important spec that must be considered when selecting an outdoor CCTV camera is its light capabilities. Does it work in direct sunlight? While many outdoor cameras come with a hood to keep the sun away from the lens many, get blinded by the reflection from water as from a pool, lake, the ocean and even cars parked nearby. On the opposite side of the spectrum, you need to keep in mind that LUX factor (ability to see in the dark) unless you select an infrared model.
Indoor CCTV cameras come in many shapes and sizes. There are three key specs you need to focus on. The first is resolution; indoor cameras are normally used to monitor and or record thus, a good quality indoor camera should have at least 520 lines for a solution. Secondly, the lens and optics; it is always desired that indoor CCTV camera has the ability to focus or zoom into a small area. This will allow you to record facial shots if they are recognizable, printable and use as evidence in a legal manner. Last, but not least, an indoor camera should blend well with its environment. This is why indoor CCTV cameras come in many shapes and sizes from bullet cameras to the domes and even disguised models that resemble everything from a motion detector, the smoke alarm, and even a fire sprinkler.