Effect of different palettes.
(click image for Flickr page or download full size 2617 x 1980 5MB PNG original
here)
Here is the same thermal image taken with the camera set with four different palettes: clockwise from top left are Iron, Black Hot, Rainbow and White Hot.
It's often said that Black Hot (top right) is the closest you'll see in the thermal spectrum to a black and white visible light image. The car is very dark grey and the sky (reflected in the windscreen) was clear (=cold) so that certainly holds true here.
All of the original images were made with a Therm-App Pro 640x480x25Hz thermal camera with 19mm lens, ThermViewer driver software (which provides superresolution to 1280x960), then Paint Shop Pro just to blur out the registration plate (which showed up incredibly clearly) and composite the four images. They were saved as PNG from the camera and haven't been compressed.
You may just be able to make out my driving spectacles, which I left on the bonnet whilst I took these images. They let me see a sparrow at 1000 feet but are absolutely useless at anything approaching arm's length. My arms aren't long enough to hold the Therm-App far enough away!
Taken at a motorway services car park near the England-Scotland border on a fine, sunny late September day. (My passengers had wanted to stop for a comfort break and, apparently, there was a queue - so I had a few minutes spare).