When you need to choose a thermal camera to protect site perimeters, it’s important to select a system specifically designed for outdoor use in order to reduce nuisance alarms and maximize detection accuracy.
Thermal cameras operate by sensing movement, but outdoors, everything moves, including the camera itself. A camera mounted on a bridge will move from the vibration of cars, trucks or trains, while cameras mounted on a pole will move from wind, aircraft taking off or other factors. In all cases, outdoor thermal cameras need electronic stabilization to maintain a high probability of detection without nuisance alerts from these vibrations.
Outdoor thermal cameras also need to ignore stray movement caused by trees and foliage, blowing debris or small animals while detecting intrusions anywhere in the field of view. For this reason, choose thermal cameras with built-in GPS analytics which know the location and actual size of the all objects in the field of view. This is the basis for size filters that accurately detect what’s relevant and ignore movement that would otherwise send a false alert.
The use of GPS technology also provides accurate target locations to show precisely where an event occurs, which is critical when protecting large outdoor areas. The same GPS information can be used to automatically steer PTZ cameras for up-close identification as an event unfolds.
You should also choose a thermal cameras that employ a high degree of image processing to produce very clear images, even among difficult environmental factors such as rain, humidity, fog and bright sun, which in the past yielded poor thermal images, nuisance alerts and mis-detects. This makes important scene details visible to both the human eye and to the analytics for automation purposes. Image processing is used to translate the high contrast thermal image into black and white video imagery optimized for the eye, providing necessary details for an actionable response.
It’s also important to choose thermal cameras built to withstand the elements. Outdoor thermal cameras can be nitrogen sealed to handle temperature changes and keep out humidity, snow, or even blowing sand.
A system like this can deliver cost savings. Long-range thermal cameras can operate at twice the distance and cover four times the area, creating a larger buffer zone for early detection of intruders, along with a direct economic benefit: Fewer thermal cameras are needed to protect the same location, reducing the number of poles, trenching and communications needed for a deployment. As a result, thermal cameras are now on par in “cost per foot” with traditional approaches to perimeter security, such as fence sensors, buried cable, or visible cameras.
