It was a thermal image, almost useless for trying to identify someone.

Black and white When not in use, the finger appeared black on thermal images.

They appear to be glowing on the thermal image because they are hot.

As anyone who has used an old fax machine knows, thermal images are prone to fading.

There's a bit more thermal image for a tad longer time, but even that eventually goes away.

The thermal images turned out to have been taken before anyone had gone to bed.

The camera has the ability to show thermal images in bright sunlight.

The combination was going to reduce his thermal image.

We're looking down on a thermal image of the targeted area.

The camera zooms in to show a man and women, who appear as thermal images, driving one of the cars.