There are two ways to spot a ghost: 1) wait for one to float up your basement stairs and say "boo," or 2) get the latest equipment and start ghostbusting. For more than 100 years, professional paranormal investigators and the merely curious have looked for the edge that would help them hunt this most elusive game. With recent technological advances, Casper may be in the cross-hairs.
Scientific ghosthunting devices first appeared on the scene in 1882, when the Society for Psychical Research was founded in England. While the introduction of the scientific method heralded the use of investigative tools such as controlled experimentation and photography, the state of the art in paranormal investigations remained fairly stagnant for the next hundred years. Investigators relied mostly on psychics and eyewitnesses. These approaches, while valid information-gathering techniques, leave much to be desired from an evidentiary point of view. Primitive scientific equipment did exist, and it was capable of monitoring and documenting anomalous phenomena, but size, portability, and expense kept such devices out of the hands of field investigators.
The field changed dramatically in the 1980s with with rapid advances in microchip technology, computer miniaturization, and dramatic price decreases in high-tech equipment. As new scientific tools were developed to detect environmental changes -- mainly for the medical, electronics, and safety industries -- paranormal investigators started using them at haunted sites. The practice of using different monitoring and recording devices is based on the assumption that any object or force that interacts with our physical environment will alter that environment in some way.
Several years of experimenting have taught us that unusual measurements can be documented at many haunted locations
While we have yet to develop a definitive specter-detector or poltergeist energy meter -- mainly because we are still not sure what ghosts are made of -- a wide range of practical and portable "ghost detection" devices are now available to the paranormal investigator.
Electromagnetic Field (EMF) Meters
Anomalous electromagnetic field readings are often recorded in haunted areas. Varying levels of electromagnetism are normal, generated by electric appliances, wiring, overhead powerlines, and the like. Normal electromagnetic fields need to be isolated and ruled out -- though it should be noted that some researchers, including William Roll, believe that strong artificial sources of EMF can induce or aggravate poltergeist activity.
Paranormal EMFs are untraceable, fluctuate in intensity, and typically move from one spot to another. They often occupy specifically defined areas of isolated, suspended space, as opposed to emanating from a structural surface. The locations of these pockets may correspond to the exact areas where a psychic claims to see an apparition. Their location and intensity can both be logged by hand-held magnetometers. One low-cost unit, the Tri-Field Meter, is routinely used by ghost investigators.
Strong EMFs can also affect magnetic videotape, causing interference bands and resulting in strange glowing or fogged images on tape that were invisible to the naked eye. Similar sound distortions, as well as strange voices (EVP, or electronic voice phenomena), can show up on magnetic audio tracks.
Radiation Meters
Abnormally high readings of gamma radiation have been detected at some haunted locations. In some cases, Geiger counter probes have recorded significant localized increases in ionizing radiation where a psychic claims to see a ghost.
Thermal Imaging
Thermal imaging cameras, developed for the medical and manufacturing fields, record and display images of objects based on their heat output, as opposed to their ability to reflect light. Using a false-color imaging template, colder areas show up as darker colors and warm areas as lighter colors, registering temperature variations as small as one degree Fahrenheit.
Investigators first used thermal cameras in haunted houses to record the anomalous cold spots that they often encountered. An unexpected development has been the detection and filming of unexplained hot spots, both stationary (on a structural surface) and freefloating. As with EMF and ionizing radiation fields, these hot spots often correspond with the exact location a psychic will see or sense an apparition. Interestingly, investigators who put their hands into these hot spots often report a cold sensation.
Color thermal imagers are still out of the reach of most ghosthunters, most often, television shows such as Sightings rent or borrow the imagers to film a field investigation. Less expensive black-and-white imagers, developed for police and firefighting applications, are not sensitive enough for paranormal investigations.
Night Vision Devices
The military developed light-intensifying lenses for night surveillance. With their stark, green-glowing image field, these units will not work in absolute darkness but will electronically amplify minute levels of available light (such as moonlight, starlight or IR emitters) to provide a functional image where unaided eyesight or photography would be useless. This allows late-night surveillance in a haunted house without having to turn the lights on. Some ghostly phenomena are reported to be more active at night, and the use of artificial lighting might inhibit a paranormal event. Night vision devices have also allowed investigators to film misty or vaporous manifestations that would have appeared washed-out or invisible under illuminated conditions.
Thermometers
Short of using expensive thermal imaging units, the best way to document a paranormal cold spot is with a rapid-reading electronic thermometer. (Forget the old mercury-filled tubes). The best type will give a constant background reading of the room and have an external probe that can be directly inserted into a cold spot. Many units will record and store data continuously, and some can be programmed to sound an alarm if the temperature drops or rises beyond set parameters.
A Definitive Answer?
While we have yet to come up with a piece of equipment that can prove the existence of a ghost (just what is a ghost?), we can detect and document the unexplained environmental changes that occur in haunted locations. We have made more discoveries and compiled more evidence in the past 16 years than in the entire history of organized ghost research. As science and technology continue to advance, it is not unreasonable to hope that within our lifetime we will be able to define, categorize, and positively establish the existence of ghosts.
EVP
EVP stands for electronic voice phenomena, its the recording of voices not heard until playback of the recording. These can be recorded on all types of recording media. The most common device now used is the digital voice recorder. An analog recorder may be used also, but make sure use a separate microphone due to internal noise from the recorder causing unwanted noise that may could be confused with a voice. The digital recorder will not need a separate microphone due to the fact it has no internal moving parts.
Disembodied Voice
A disembodied voice is an unknown voice that is actually heard that cannot be explained.
Cold Spot
A cold spot is a mass of cold air that has no logical explanation. The theory is that when an entity tries to manifest that it draws the warmth from the air producing a cold spot. Cold spots often travel from one area to another.
Apparition
An apparition is the appearance of a human shaped form by seeing with it the naked eye or by being photographed or by video. At times, an apparition will appear as a solid human form or have a vaporous appearance.
Orb
The orb is a very controversial subject, they appear both on digital photos as well as film. Most orb photos however seem to appear on digital cameras. Orbs are generally considered nothing more than illuminated dust particles, however some have been seen with the naked eye that seem to be producing their own light and have an intelligent flight path. These are the only ones that we consider valid. We cannot not say this is evidence of a haunting due to the fact that this may be an unknown natural occurrence.
Residual Haunting
A residual haunting is an occurrence that may be somewhat described as a tape continuously playing an event in time. The entity is not aware of your presence and makes no attempt to interact. Some researchers believe that a residual haunting is not an actual entity at all, but just a look at the past like a video thats brought on by means which we still do not understand. The term residual many believe also applies to noises, phantom smells, even animal sightings.
Intelligent Haunting
The term intelligent haunting refers to an interaction between an entity and humans, it will show the ability to make noise, move objects, in some cases speak audibly. Examples would be an evp question with a direct answer, asking for a sign of its presence and getting a reply, in other words, it has the ability to react to the living.
