reply to post by tinhattribunal
Interesting. Yes that would work. To a point. You do have to move eventually. And it depends on other factors such as ambient back ground temperature,
camera settings, software, etc.
If you are discussing Thermography, that is a little tougher to hide from. Your body heat rises and can get around a piece of plastic. Unless you seal
yourself in, in which case you might die of suffocation before they can find you. Anything that prevents your "heat signature" from being visible is
useful. Hiding behind a tree is enough if you know where the surveillance is coming from. A chopper over head may be running without lights or far
enough away that you don't hear it. People with scopes or thermal imaging equipment see different things, depending again upon the settings,
software, background temperature, etc.
You could dive into a body of water, you could wear a wet suit (or dry suit). You could hide in a culvert, or blend in with a "hot spot" like an air
conditioner or car that has recently been driven. Your heat signature would "merge" with the other thermally "hot" item and make you harder to
pick out of the background clutter.
As long as you don't peek out or stand up suddenly. Many layers of clothing tend to trap heat as well but would be useless if you didn't wear gloves
and cover your face. Look at this image:
The officers are guarding a Nuclear Waste train. Their "mid sections" are opaque to the imager because they are wearing bullet proof vests. Hers
another taken with different temperature setting on the camera:
Notice the difference between the two. Before you begin filming a camera has to be programmed for background and "threshold" temperatures. Setting a
hi lo range for the display to represent the colors for differing temperatures( if in color mode). So, below a certain temp, the back ground can
appear black or be assigned a color. Its kind of like a gain control or "brightness" setting. Thermal imagers see "Heat" not visible light. They
operate in the Infrared spectrum. Heat behaves like light. Thats why you feel the heat from a fire on your skin. The radiant heat energy travels
through the atmosphere just like light photons. At the same speed as light.
The camera sees and displays the difference in temperatures in its field of view. So the face of a person is hotter or higher on the color scale than
the persons clothing and higher than the ground or buildings. If a roof is hotter than a wall for instance then that is displayed in the next color on
Thats how you can see the train has moved recently, the colors of the brakes being applied are "hotter" than the cars themselves. The heat from the
nuclear waste is warming the containers and the train car walls because it is heating it up from the inside. Like a warm coffee mug. You are not
seeing the Radioactive waste inside its container, you are seeing the warm skin of the outside
of the rail car. That tells you something inside
there is warm.
Like these two pics:
The top one is of a half full water tank in visible spectrum and the bottom thermal image shows you the water line. You aren't seeing the water in
the tank, just the difference in temperature of the outside of the tank at the water line.
Sorry for the long post, thought the information would help some to better understand.