That brings back some 40+ year old memories.
Back then Kirlian photography was sometimes in news related to paranormal phenomena.
IIRC, Kirlian was a Russian electrician.
Some have used the technique to make some nice fine art photography.
Kirlian photography is a way to make photos of an electrical corona discharge.
An object is put on a photographic plate or frame of film set on a conducting plate, and then the subject to be photographed is connected to a high voltage source of electricity.