If you are confused about the variety of CCTV Camera types on the market today, then you’re not alone. Cameras come in different shapes, sizes colours, protocols, transmission methods, resolutions and capabilities. The choice on offer has never been larger with each camera generally specified for a certain scene or purpose. Here we cover off some basic differences talk about the pro’s / cons of each.
The first and foremost question anyone should ask when selecting CCTV hardware is which protocol to use: Analogue (also called AHD or TurboHD), IP (also known as digital) or Wi-Fi (also known as wireless).
- Analogue CCTV is one of the oldest forms of CCTV Technology however is still in widespread use today.
- Analogue CCTV has a theoretical maximum cable distance of 1000m with the use of an amplifier.
- Analogue CCTV generally uses coaxial cable (like analogue TV cable) to transmit images from the camera to a Digital Video Recorder (DVR).
- Power to these cameras is also generally provided by a separate cable running 12v DC.
- Although coax cable is widely used, installers have used the 8 cores in an ethernet cable to save cable and installation time.
- Analogue CCTV is generally cheaper than its IP counterpart.
- IP CCTV is a newer technology which uses a LAN network to connect cameras with a Network Video Recorder (NVR).
- IP CCTV generally has a maximum cable distance of 100m between nodes (such as network switches, extenders and repeaters); however, manufacturers are investing to increase this.
- IP CCTV generally uses CAT5e ethernet cable to run cables between devices.
- IP Cameras are largely Power-over-Ethernet (POE) meaning a separate power cable is not required.
- IP cameras are generally more expensive than analogue; however, as a rule of thumb has the superior image quality and functionality.
- Wi-Fi cameras use a Wi-Fi network to transmit their images either to a storage device (such as Network Attached Storage (NAS) or to a client (mobile phone).
- Wi-Fi cameras allow for quick installation for minimal investment.
- Wi-Fi cameras still require a power source.
- Battery-powered/solar-powered cameras are designed to run on so little power that images are typically only recorded when motion is detected. It should be noted that the motion detection capability is performed by a camera which is already in a hibernate state and as a result, motion can and does get missed.
- A constant stream over the Wi-Fi network can cause speed issues for other devices on your network.
- If a cloud service is used, the camera will have an impact on upload speed.
CCTV Camera Types – Pros and cons
CCTV Camera Types – Other things to consider
ANPR stands for Automatic Numberplate Recognition. Cameras with this specific capability use an onboard microprocessor and a set of algorithms to identify and read a number plate within a camera’s view. Further workflows (such as opening a barrier) can then automatically take place dependant on if the vehicle registration number is within a database. This technology has been used by law enforcement agencies and car park companies with great success over the past decade.
CCTV motion detection uses the perceived movement in a field of view by detecting changes of light. This function is performed at the recording unit (NVR or DVR). Most NVR’s and DVR’s can be programmed to notify another device (such as the user’s mobile phone) or ‘flag’ the incident within the archives for review. Motion detection is prone to false alarms from light changes (due to a vehicle moving nearby) wind and pets. Where a motion detection alarm is critical, consumers should consider hardware with human and or vehicle identification alarm capability.
Human Identification Alarm
Cameras with human identification alarm have a built-in microprocessor that analyses the scene separately to the NVR. It uses complex algorithms that factor shape, size and movement to determine if a human is in view. Once a human is identified, the NVR will check against its predefined rules (such as if the human is in a certain area of the camera’s view, within a set time) and will notify device users if configured. This feature greatly improves upon general motion detection.
Temperature screening or thermographic cameras detect elevated skin-surface temperatures. Since April 2020, employers have increasingly depended on this technology detect the presence of covid-19 in addition to other fever inducing conditions. Thermographic cameras are just one example of how CCTV is providing a benefit to consumers beyond evidence after the incident.
One of the most often overlooked component when choosing a CCTV camera type, but one of the most crucial is lens depth. A photographic lens is a device that focuses the available light onto the camera’s sensor and in doing so, determines the viewing angle and optimal distance that the camera. A smaller lens depth (such as a 2.8mm) will provide about a 90-degree viewing angle. However, it will only provide an image capable of identifying someone up to about 3m. A larger lens (such as a 16mm) will provide a clear image at large distances but only give about 20 degrees of viewing angle.
Equally important to lens depth is light capability. Cameras depend on light hitting the sensor and producing an image, some of which do this better than others. Cameras with a poor light capability may ‘trip’ over to infra-red mode in dull conditions and in doing so, lose the colour capability. For a proper installation, measure ambient light levels and select a camera with the required lux levels selected. If this is not done, users may find their CCTV rendered insignificant during the period that they are most vulnerable.
Another useful function that IP CCTV has brought to market is the use of two-way audio. The ability to record sound in addition to a video can not only add to existing evidence, but it can also be used to stop or deter crime as it happens. Other benefits include having a two-way conversation with staff and customers in remote or unmanned areas.
Active deterrence produces an audio and visual alarm at the CCTV camera once a set of predefined conditions are met. Most hardware with this feature also allows for users to record their message to add maximum impact. Due to the false alarm ratio regarding general motion detection, active deterrence should only be combined with human or vehicle identification.