If you wish to collect evidence of ghosts, you must first understand how paranormal investigators prove their existence. The proof of ghosts is a mixture of equipment and personal experiences.
Audio Evidence of Ghosts and Hauntings
Investigators seek audio evidence to show ghosts may be real. Such evidence may be recorded on instruments, or witnesses may hear it. Many believe these audio phenomena may indicate ghosts are real and are trying to communicate.
Electronic Voice Phenomena (EVP)
Many paranormal investigators believe that the audio recordings known as EVPs (Electronic Voice Phenomena) indicate ghosts are trying to communicate. Investigators believe EVPs provide evidence that ghosts are real. Of course, EVPs are not the only form of audio evidence. An EVP occurs when voices or sounds not heard in the moment appear on a recording media, such as a tape, video, or voice recorder. While the majority of this type of evidence are ghostly voices, there can always be other sounds, such as animal noises, crashes, doors opening, and closing, and other sounds that appear on the recording media that don't match actual physical events that occurred at the time of the recording. EVPs are classified into several types depending on how clear and understandable the audio is.
Ghost Box Voices
A ghost box scans AM and FM stations to generate a white noise background. It's through the frequency created by the scanning that spirit voices often emerge as they attempt to communicate in an intelligent haunting by responding to questions the investigator asks.
An Ovilus is an instrument that has a library of pre-programmed words. Some paranormal investigators believe ghosts may be able to manipulate the words in the device to communicate. Digital Dowsing created the Ovilus, but there are similar instruments available.
Smartphone apps, such as EchoVox, which use various forms of sounds to allow spirits to create words and communication. You can explore the various apps available for ghost hunting voice recording.
There are many instances when people hear disembodied voices without the aid of any equipment. Occasionally, investigators capture disembodied voices on a recording media. These differ from EVPs since at least one person heard the voice at the time of the recording. Many believe this type of evidence is the gold standard of proof of ghosts.
Photographic and Video Evidence
Orbs are a common phenomenon in images from haunted locations. Many times, orbs are photographic artifacts, reflective dust particles, or bugs. Nevertheless, many believe some orbs may also be paranormal evidence. There are self-illuminated orbs that someone sees with the naked eye that are also captured in photos or videos. These are described as spirit orbs and are quite different from orbs that appear solely in photos or video.
Light anomalies are another controversial piece of evidence. These appear as light streaks, rods, or other similar odd-looking bits of light or blur. In photographs and video, they are often associated with movement, light settings, ambient light, and shutter speed; however, some people feel these may also offer evidence of a haunting.
Partial or full-body apparitions are the prized captures in a video or photograph. Paranormal investigators always hope to capture one during an investigation. These most often appear in photos as shadow figures, transparent figures, or misty figures. They are seen either as a full bodied apparition, or just a few body parts, such as a head or a hand.
Electromagnetic Field (EMF)
Many investigators also measure the Electromagnetic Field (EMF) and consider changes in these fields as evidence of ghosts. As with other potential evidence, the presence of a high EMF is still a controversial finding. To use this technology, you must take a baseline reading prior to your investigation so you can compare any fluctuations and changes in this field of energy.
Personal experiences offer a different type of evidence of ghosts. The problem with personal experience is their subjective nature. With no way to record or measure it, the evidence is treated at best as anecdotal. However, if a personal experience occurs in conjunction with other findings, it may provide stronger proof of spirits. Personal experience includes receiving psychic information, experiencing cold or hot spots, hearing voices, or seeing things not caught on recordings, experiencing doors opening and closing, hearing phantom footsteps, and similar experiences.
One type of personal experience does leave evidence. It cannot be easily discounted as anecdotal. This evidence is when an investigator suddenly has strange, red scratches, often three in a row. The first sign of this attack is a burning sensation, often on the back. These scratches are made by what is believed to be a malevolent spirit.
Scientific Evidence of Ghosts
All the previous pieces of evidence are technical or anecdotal; they are not scientific as currently there is no evidence of ghosts gathered using the scientific method that meets necessary criteria such as repeatability and falsifiability. To date, no scientific evidence of ghosts exists.
Evidence Ghosts and Proving Their Existence
Paranormal investigators use various technical equipment and methods to measure possible evidence of ghosts. The devices are used in conjunction with personal experiences to give a complete picture of a haunting. The journey to proving the existence of ghosts is challenging, but there is undeniable proof that something not understood is happening in these haunted places.