A decomposed homicide victim remains recovered from a crime scene long after the homicide. The identity of the victim could not be done visually, so a dental identification was done and confirmed with the prison numbers tattooed on the segment of mummified skin recovered. The IR photographs detailed the prison numbers that were otherwise unable to be seen with normal light.
The IR ("infrared") photographic used special photographic techniques and IR light to create an image of the damage up to 3 mm below the surface of the skin, basically, bleeding under the skin. In this case, the IR light captured the pigment under the skin from the tattoo.
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