Low light requires natural light and transforms weak natural light images into enhanced electronic images through image intensifiers. Active IR actively emits infrared light and uses infrared beams reflected by targets, offering poor concealment. Thermal imaging doesn't require any light and is a passive infrared night vision system that detects infrared radiation differences between targets and scenes or different parts of an object. It is not affected by changes in surrounding lighting conditions and performs reliably during night or in fog, rain, and other harsh environments.

In most cases, thermal imaging cannot be blocked. However, infrared rays cannot penetrate walls, and glass can block IR. To avoid detection, you can conceal behind glass or walls to block thermal imaging.