One of the most commonplace "real ghost pictures" are what psychics call ‘orbs’. Orbs are usually circular balls of light. Most are usually white orbs though often orbs are red and many other colours. Some orbs appear to have images and faces within them. The orb can be a paranormal phenomenon but most of the orbs caught on cameras may have an earthly explanation.
One popular orbs theory is that the orb is the energy being transferred from a source such as power lines, heat, batteries and so on. Energy like a globule of water in zero gravity is drawn together to form a sphere. Orbs may also have something to do with human bio energy and may be an effect of the energy of the aura. The difference between this spirit light phenomena and orbs caught on camera is that spirit lights can be seen with the naked aye and by everyone present.
In some rare instances the orbs that appear on camera are hard to explain. For example why do orbs appear when a healer extends their powers but are absent when they stop healing. Why too do photographs of mediums working also result in photographs of orbs. And why do large numbers of orbs appear at spiritually significant events under conditions that would normally not allow for orbs to be created by dust, moisture or faulty cameras? (Note: A Light In The Darkness does not necessarily agree with the above opinion.) (Psychics.co.uk)