System designers have a variety of choice when specifying the most appropriate cameras to monitor large areas, Uri Guterman, of Hanwha Techwin, provides an overview of the merits of some suitable camera formats.
PTZ cameras have been used for city and wide surveillance applications such as airports, car parks and sports stadiums, with operators able to track the movement of objects and zoom in for close-up detail of anything. The ability of an operator to proactively monitor an incident and zoom in to verify what is occurring, ensures they are able to decide on a response. In addition, many PTZ cameras feature auto-tracking, as well as continuous pan and pre-set positioning, meaning that images of a moving object will be captured even when operators are distracted.
Few users would deploy 8K cameras with the intention of monitoring a field of view. The value of these come from that 8K is the equivalent of 16x 1080p full HD images, meaning that a single camera can capture a vast amount of information, enabling operators to zoom into a small part of the scene without any pixilation of the image. A football stadium is an example of where an 8K camera can be put to very good use as it would be capable of capturing evidence grade images of 20,000 or more fans occupying a football stand. As such, its price/performance ratio makes the 8K camera a viable, cost-effective alternative to the deployment of multiple fixed or PTZ cameras.
When it comes to deciding whether an ultra-high resolution 8K or PTZ is the best camera format for any location, it will very much depend on what the user wants to achieve. Budget limitations also need to be taken into consideration. Simply, an 8K camera is a highly impressive, high performance option if there is a requirement to continually record a camera’s entire field of view at the same time that an operator might need to zoom into a specific area of interest. However, PTZ cameras are a much lower price and are ideal for when operators need to constantly scan a wide area of view, whilst flexibility when necessary, to quickly zoom in to see what is occurring in great detail.
Multi-directional cameras offer the capabilities of two, three or four video surveillance cameras and yet, you will only need to purchase one VMS license. Those equipped with two separate lenses are designed to capture HD images of adjacent areas. There is a choice of interchangeable lens modules which can be fitted on site. These cameras significantly reduce the costs which would be associated with installing two separate cameras to monitor.
There are multi-directional cameras available which feature four separate sensors, with operators able to choose from a broad range of customisable angles and zoom settings per sensor. This offers cost savings for both system integrators and end users, as multi-sensor cameras use less cable, conduit and mounting hardware, compared to what would normally be required to enable up to four separate cameras to do the same job. Designed for monitoring large open areas with just one camera, the images captured by the four sensors can be stitched, producing an image covering up to 220°.
It’s worth noting that manufacturers, such as Hanwha Techwin, offer 4 channel multi-sensor cameras with an additional integral PTZ camera. This can automatically zoom and track an moving object or move to a user configured pre-set position when the motion detection function of one of the four camera sensors detects activity.
A single 360⁰ camera often offers the most efficient and cost-effective way of monitoring a large area and particularly when a number of standard cameras may be required to avoid any blind spots. They offer a compact option for retail stores and environments where aesthetics are important. Savings can be achieved on maintenance costs compared to other types of cameras, as 360⁰ models have no moving parts. 360⁰ or ‘fisheye’ cameras offer alternative viewing modes. They are likely to feature a digital PTZ, allowing operators to pan, tilt and zoom in on areas for a more detailed view, whilst continuing to record the whole 360-degree view.
With different camera formats to choose from, you have an interesting challenge in deciding which cameras will meet the requirements of a video surveillance project. To an extent, the decision can be made with the help of the risk assessment process, by taking into account an end-user’s operational requirements. An 8K camera, would seem the choice when there is a need to monitor large crowds of people in wide open areas, whilst multi-directional cameras are ideal for capturing images of adjacent areas. PTZ cameras are likely to be strong contenders when the captured images are to be viewed in real-time, as they provide operators with a high level of control, enabling them to proactively track the movement of people.
As always, the best advice is to work with manufacturers you can trust and ask them to provide live demonstrations of their camera types. This will allow you to make informed judgements on which cameras have price/performance ratios that will match your requirements.