Pub drinks. Thermogram of three men with cold drinks at a pub. The man at centre is wearing sunglasses and his head, face and body is cooler than the other two, possibly because he may have just arrived from cooler temperatures outside. Thermography records surface temperatures by detecting the long-wavelength radiation emitted by an object. Here, the colour-coded temperature scale runs from white (warmest) through pink, red, orange, yellow, green and blue to black (coldest).