The traditional approach to long range video surveillance was to use a high specification camera fitted with a telephoto lens. The optics usually cost more than the camera and typically weighed more too. However, a new device from respected lens manufacturer Fujinon delivers a compact camera with long range capabilities. Despite being the company’s first entry into the camera market, Fujinon’s track record makes it worth consideration.
Given the common need to monitor large and open areas, the popularity of zoom cameras has been consistent for many years. In the past, suitable devices carried a steeper price tag than other image capture devices, and often integrators would opt to install numerous devices across an area in an attempt to keep systems cost-effective. However, due to constraints in terms of site layout, this wasn’t always possible, and typically introduced additional costs for infrastructure. This often made solutions over-priced if the budget wasn’t sufficient to support the extended cabling topology.
Long range video capture does offer a number of benefits, but it also introduces a few considerations which must be addressed with regard to performance. Cameras offering long range image capture must be swift to focus and align, offer good levels of image stability, capable of managing varied environmental conditions, and able to capture images of a similar high quality to those captured over lesser distances.
With many long range devices, the limits of optical zoom are compensated by adding digital zoom. This does offer extended ranges, but at the expense of quality as each digital magnification introduces a constantly increasing level of pixilation.
With expertise in long range optics, Fujinon has addressed these issues in the design of its long range SX800 camera.
Enhanced performance
The SX800 has been developed with cutting-edge optical and image processing technologies. It features a high-performance integral Fujinon zoom lens capable of 40x optical zoom, offering a focal length range extending to 800mm. It also features advanced image stabilisation performance, fast and accurate autofocus (AF) with speeds up to 0.3 second, and heat haze and fog reduction functionality.
Long-range surveillance cameras capable of monitoring distant subjects are undergoing an increased demand from end users. However, conventional cameras have issues including susceptibility to camera shake and slow autofocus. Fujinon has worked on developing innovative features to resolve such issues by combining optical technology, achieved through the development of a wide range of lenses including 4K and 8K-compatible broadcast lenses and cinema camera lenses, with advanced image processing technology found in the X Series of cameras.
The SX800 offers a focal length range from 20mm to 800mm. When combined with the digital zoom of up to 1.25x, the camera can reach the focal length equivalent to 1000mm in long-range surveillance. This means it can capture the vehicle registration plate on a vehicle over a distance of 1 kilometre.
Making use of a proprietary image stabilisation mechanism reduces the impact of camera shake without any time lag. Furthermore, the use of a rear focus mechanism and other features ensures high-speed and high-accuracy auto-focus functionality.
The camera’s high-speed image processing engine supports detection and real-time correction of heat haze, fog, and other environmental conditions which may be detrimental to long range image quality.
These features make the camera ideal for surveillance at national borders and large-scale public facilities including ports, airports and highways.
The SX800 features a newly-developed image stabilisation mechanism which uses optical and mechanical design technologies which have been created by Fujinon via the development of broadcast lenses and interchangeable lenses for digital cameras. High-performance gyroscopic sensors detect the smallest levels of vibration. The use of ceramic beads, processed in precision, in the mechanism’s drive section minimises friction and resistance during image stabilisation for accurate compensation of camera shake without any latency. This allows the camera to be installed in high positions susceptible to winds or in locations which suffer vibrations.
The rear focus AF mechanism drives a rear group of small-diameter lens elements at high speeds. The combination of on-sensor phase detection AF and contrast AF achieves autofocusing in a very short time, attaining focus on a subject almost instantaneously. This is a substantial improvement in AF speed compared to several seconds to around 10 seconds it takes for conventional systems which drive a front group of large-diameter lens elements.
The mechanism is capable of continuous AF, maintaining focus on a subject in real time. The camera automatically switches to the optimum AF system according to the site’s lighting conditions and other factors.
The lens features a multi-layer coating to support a wide range of wavelengths from visible lights to near infrared.