Urban Myth?

[Paul]

Problem is most FLIR can differentiate between same heat or no heat.
For example, if the ground is warm, you cover it with a metal foil, the FLIR sees a dark square.
The foil stops the heat from being visible.
Same for you standing. Background hot, you cold (just add a bit of wind chill) and you're black on white (depending on the setting on the FLIR).
OR it just appears as a black hole because you've blocked the radiant heat from the background.

Bottom line, you're FUBAR when the A10 opens up on you.