Vortex ... 
Source: http://www.ourcuriousworld.com/TypesofGhosts.htm
Somewhat less common than orbs are those little clouds or wisps of light that sometimes appear in photos known as vortexes (or, sometimes, vortices). Usually appearing as a swirling spiral of light (though they can also be more substantive as well, sometimes taking on the form of an apparently opaque shape, often of considerable size) they, like their cousin the orb, are also thought to be spiritual energies in the process of manifesting themselves, but ones that are closer to achieving that goal than are their spherical cousins.
In other words, a vortex can be thought of as an orb that is in the process of moving 'outside' the confines of its energy bubble in an effort to take on a more human-like form.
Like orbs, vortexes too are usually dismissed as reflections of light off either exhaled breath or cigarette smoke, while the more substantive opaque shapes can be explained away as camera straps or some other object that has inadvertently fallen in front of the lens (human hair makes for especially good and 'spooky' vortexes).
Again, like the 'orbs as dust' theory, this explanation probably does account for the majority of vortexes caught on film (especially those taken by amateurs). It's extremely easy to forget about objects inadvertently placed in front of a camera lens and then enthusiastically proclaim the resultant anomaly a 'ghost', so this explanation does carry considerable weight.
However, vortexes have their defenders as well, who maintain that 'true' vortexes look nothing at all like exhaled breath or cigarette smoke, but instead have an eerily unique and unusual pattern all their own. Additionally, they also point out that vortexes shot by careful investigators need to be taken seriously, since such people are usually meticulous about ensuring that camera straps are removed and people are not smoking in the vicinity at the time the photo is taken. Then there are even those vortexes that seem to be forming limbs and other recognizable human features to consider.
Though these can be the result of the eye wanting to bring order to a random swirl of mist (a type of rhorsach effect) some of the best vortex photos truly do appear remarkable, so it would be unwise to dismiss all of them as simple tricks of the eye or ham-handed incompetence.
Image credit : http://www.ghosttowns.com/states/tx/peytoncolony.html
Source: http://www.ourcuriousworld.com/TypesofGhosts.htm