Infrared

Night-vision devices using infrared illumination allow people or animals to be observed without detection. Infrared radiation is popularly known as "heat radiation", but light and electromagnetic waves of any frequency will heat surfaces that absorb them.

I came across this video on youtube whilst searching about infrared :

The effect of the camera appears to portray the cat as quite ghost like. This reminded me of the idea od genius loci and spirits and how they could be portrayed.