The Ghost Hunters Academy "kit" contains, among a few other devices, one non-contact IR thermometer, apparently without probe. Why would they do this, I asked myself. Well, a probe costs a bit more so maybe by not including it they could cut down on cost? Really that's about the only explanation I could come up with.

One could make the assumption that, since this thermometer is designed for measuring surface temperatures, that it would be of no use detecting a moving, free-floating cold or warm spot. But would the change in air density from the introduction of a cold or warm entity be enough to allow some form of detection with this thermometer? Well, instead of just guessing, I wanted to verify it by trying to measure a ghost in my kitchen.

Since I could not be sure of the ghost's presence (these things don't happen on cue, after all) I had to simulate a ghost. There is a theory in this area. One is that there is a cold spot formed when the entity draws energy out of the air to manifest. Remove energy, temperature goes down, air gets colder, cold spot. I have no problem with that as a theory. So the area around the ghost would be cool, and the ghost itself should be warmer since it is absorbing energy.

How to test this, though? Well, I turned on the oven to 400F with the door shut and allowed it to come up to temperature. In the meantime I stood alongside my freezer and aimed my IR at a wall across from the freezer. The idea being that I could open the door, cold air would spill out into the area in which the beam was passing through and I could see if there was any temperature change. The thermometer was fluctuating by a few tenths of a degree F and, upon opening the door, this fluctuation did not change in any noticeable way. The air spilling out was probably about 60 degrees F cooler than ambient air temperature.

When my oven came up to temperature, I knelt in front of it, aimed the IR over the counter at the opposite wall and got a sense of the temperature being registered (in the 76.5 to 77 degree F range) I then reached out, pulled open the oven door and allowed the air that was a good 300 degrees F warmer than the ambient air temperature rise out of the oven into the area I was aiming through. No detectable change in the fluctuation range that was being measured by the thermometer.

So, is an IR thermometer without probe of much use? I suppose if the entity were standing next to the wall so that part of the energy being "drawn in" by it was from the wall itself, then yes it could be useful in detecting it. If the entity were sitting on a chair, sofa, etc and drawing energy (heat) from it, yes it might be useful (assuming the energy absorption theory has any validity) Otherwise, not much use for ghost hunting.

It is very useful, though for determining areas of poor insulation in your walls :) I say that in jest, but if you DID detect a cold spot on the wall while on a "hunt" you'd have to do some checking to make sure it was not just an area of less insulation.

I believe in one of the GHA episodes we saw Eric(?) using the IR thermometer exactly thus, with no probe. Why? Was that what he was taught to do?

An additional test was performed today because I was in the mood for soup this afternoon. The previous tests simply involved hot air. A brief discussion about a DT episode (Haunted Forest in Japan) and detection of gaseous entities with the model of FLIR currently in use got me to thinking. Steam is a vaporous substance, would the current FLIR detect it.

So I performed some tests with the non-contact IR thermometer to establish a base temperature sweep over the stove into the far room. Then started boiling some water. As the water started to get to a boiling temperature (but prior to boiling) I conducted some repeated sweeps and detected a change in temperature (of about 2F) above the kettle. I continued to let the water heat and eventually come to a full boil and this time detected about a 5F temperature difference above the kettle.

Obviously the water vapor was a lot higher than 5F above the temperature of the far wall, but the registered change was enough to be deemed significant and proof that a non-contact IR thermometer could detect it, and by extension, I am very willing to bet that the current FLIR used by GH/DT would also detect it.

An interesting observation was the temperature difference. I'm not entirely sure how it would have registered on the FLIR (ie if it would have been much greater based upon the mechanics of operation, mine being strictly a point measure) but if it was similar to how the IR thermometer registered it, a hot vapor plume would appear as a cool entity…you know, the type that like to wear dark shades :)