Understanding how to interpret a thermal image is just as important as knowing how the camera works. A thermal camera doesn't show ghosts, cold spots, or "energy patterns" by default - it shows heat. Everything you see on the screen is simply a visual translation of the infrared radiation being emitted from surfaces in front of the lens. Once you get used to reading that information, you'll find thermal cameras can be a useful investigative tool, but only when you know what the colours actually mean and what they definitely don't mean.

Technically, a thermal image isn't a photograph. It's a map of surface temperatures of solid objects in the field of view, coloured according to the range selected by the camera. Warmer areas glow in yellows, oranges, reds, or whites depending on the palette, while cooler areas appear in blues or blacks.

The key to reading a thermal image is remembering...