You might have heard that thermal cameras are sensitive to weather conditions. This is true - the image quality of a thermal camera is strongly dependent on weather conditions such as rain, fog and air pollution, but that does not mean that the visible light camera provides better detection performance in such situations.
Figure 3: A comparison of detection capability in light mist.
The images shown here compare an Axis thermal camera (384x288) to a 1280x800 visible light camera. As you can see, despite the difference in resolution, the detection capability of the thermal camera again outperforms the visible light camera.
Visible light cameras are often subject to false alarms caused by, for example, branches moving in the wind, headlights from cars, or a plastic bag flying by. Thermal cameras, on the other hand, can provide more reliable detection and recognition by adding image intensity to motion detection. This results in fewer false alarms and reduces unnecessary responses and actions by personnel.