There has been a significant increase in those that are interested in collecting thermal evidence in order to prove the existence of paranormal or supernatural beings, thanks in part to technology and popular television shows such as CSI.  When we speak of thermal evidence, we are referring to using thermal imaging devices, such as cameras, to display paranormal activity.

Most people who are interested in using thermal imaging devices are unaware of how these instruments actually work.  As many believe these devices are simply heat viewers, while they really display infrared light. There have been reports of unexplained figures and anomalies within the images that are picked up by thermal imaging devices. It has become a widely held theory that these unexplained anomalies are evidence of paranormal or supernatural beings as they move throughout our world.

Although these devices are highly coveted, very few individuals investigating paranormal activity have such equipment, since it is pretty expensive. And, even fewer people truly understand how the equipment works. So, it is recommended that you refrain from claiming to be able to provide proof of paranormal activity until you fully understand how thermal imaging devices work, if you are new to this type of investigating. 

Since thermal imaging devices have the ability to provide false positives, due predominately to the functionality of the equipment. Thermal evidence is arguably among the most disputed among those who believe in paranormal activity and skeptics. It is wise that investigators use thermometers, for the detected cold spots, and night vision cameras for any anomalies, in order to further validate any evidence that may be found using thermal imaging devices.