Many people capture illuminated, circular spots in their photographs. These spots are commonly known as orbs. Some people explain orbs as light reflected off surrounding surfaces; some explain them as light reflected off dust particles; and some explain them as spirits or other entities normally invisible to the human eye.
Little research has been done on this phenomenon, but Dr. Gary E. Schwartz and Adjunct Research Professor of Optical Sciences Katherine Creath at the University of Arizona did publish a study on orbs in 2005.
They said most orbs can be explained by the reflection of the camera’s flash off of objects on the scene, or off of dust. However, Schwartz and Creath acknowledged that some orbs seem to defy conventional optical explanation.
An orb captured in a BBC documentary, for example, moved slowly before disappearing. Schwartz and Creath write: “It is not possible to explain orbic objects such as these that move in dynamic and unpredictable paths as being caused by stray reflections. It is also not possible to explain many of them as being caused by dust particles in the air.”
This documentary was filmed using a high-end infrared camera mounted on a tripod, eliminating some of the factors the researchers say often cause orbs in photos taken with inexpensive cameras.
Schwartz and Creath continue: “It is neither logical nor responsible at this point to conclude that every [orb] … observed worldwide can be explained by a conventional optical science mechanism such as stray reflection.”
In their view, however, most orbs can be explained by conventional optical science and new explanations for the anomalous orbs may develop.