First and foremost, this is an opinion of the author (myself) and not a scientific fact. So you make your own judgement call on the topic.
According to Paranormal-Encyclopedia.com, it defines orbs as synonymous with sphere, when used in association with the paranormal, an orb is an anomalous globe-shaped spot, either white or colored, that shows up in photographs taken at allegedly haunted locations. Even though ghosts have been capture on celluloid film since the time of George Eastman in the 1880’s, orbs only started appearing since the invention of the pocket camera with built in flash.
If you pay attention to the occurrence of orbs, they usually appear in still digital photography. As technology has progress we now see them moving while being filmed with digital video recorders. When digital cameras became popular in the early ’90s, ghost hunters and other paranormal investigators were able to quickly take dozens of pictures in a single location. The orb became popular as more than an anomalous spot.
The article has a quote from Fuji Films in response to a customer’s question.
“Floating dust particles may cause white spots appearing at different positions on pictures taken by a digital camera using the flash. Dust in front of a subject reflects the flash light and the image of the dust is captured out of focus.
Dust, snow, rain, pollen, condensation, or any small airborne particles may cause the same problem.
The particle will appear light and big because it is out of focus; it may assume a shape similar to the aperture of the camera, usually round.” (Orbs, n.d.)
Another website makes the following statement:
“True orbs are spirits of the deceased (both human and animal) in the form of spheres, or balls of light that can hover and fly at will. Orbs can be transparent or translucent and can be seen in photos and videos. They usually can’t be seen by the human eye alone. Some say you can even see faces inside some orbs. Photos of orbs are the most common paranormal photos out there. The number of orbs have been known to multiply greatly during moments of high paranormal activity. Orbs can be found outside and indoors as well. A theory for why a spirit takes the form of an orb is that it takes the least amount of energy to manifest into.”
The author of this web site quoted another site called Magick Garden.
“In my personal experience, I can definitely state that: During paranormal events, orbs are usually present. On every investigation where we have determined paranormal activity to exist, we have gotten several orb photos. There is a correlation between the amount of electromagnetic activity and the number of orb photos taken. We have never taken an actual orb photo in a place where there was no paranormal activity. During one investigation, we followed an orb using an EMF meter and a digital camera. It led us on a tour around the grounds of the property we were investigating. My personal opinion is that an orb is just one way a spirit can manifest in the physical universe.” (Orbs, 2012)
Now Fuji describes the artifacts as a common photographic problem:
There is always a certain amount of dust floating around in the air. You may have noticed this at the movies when you look up at the light coming from the movie projector and notice the bright sparks floating around in the beam. In the same way, there are always dust particles floating around nearby when you take pictures with your camera. When you use the flash, the light from the flash reflects off the dust particles and is sometimes captured in your shot. Of course, dust particles very close to the camera are blurred since they are not in focus, but because they reflect the light more strongly than the more distant main subject of the shot, that reflected light can sometimes be captured by the camera and recorded on the resulting image as round white spots. So, these dots are the blurred images of dust particles. (Flash reflections from floating dust particles, 2005)
This debate has gone on for many years and will continue for many years to come. As you can see there are many differing opinions. Some science research groups have written lengthy articles claiming they have evidence that proves it is not paranormal. Then there are those who attempt to disprove the logic of these researchers.
Honestly, I am from the school of thought that orbs are not paranormal, but I will never commit 100% to that fact because with the paranormal anything is possible.
Flash reflections from floating dust particles. (2005). Retrieved from https://web.archive.org/web/20050727000507/http://home.fujifilm.com/products/digital/shooting/flash.html
Orbs. (n.d.). Retrieved from http://www.paranormal-encyclopedia.com/o/orbs/
Orbs. (2012). Retrieved from http://www.studiesoftheparanormal.com/orbs.html