Camera Phenomena and Pop Culture Mythology

Above you see what many folks out in the world would think is some sort of paranormal apparition (no, not the cat the light streak). Its not, and I want to do my part to stop this nonsense. The urban myth of paranormal 'orbs' in photography has really exploded with the popularity of handheld digital cameras. For the layperson, the above image would be impressive, but let me share with you what I know about the image. First the aperture of this image is F2.8. Thats a really, really wide open aperture, and because of that, objects in the image easily fall out of the narrow depth of field of the image. So what you are seeing is most likely dust, reflecting the camera flash. Why the trail? Because the image has a shutter speed of 1/30th of a second. That may not seem long to you and me, but to a camera thats a heck of a long time. So, the dust was moving at the time of the exposure. Why was it moving? Ha! Because the intake for the heating system is in the room that it is traveling into. So, what you have is reflected dust, caught in air currents, moving toward the intake for my central heating system. Not a ghost. If you came here to see a photo of a spooky 'orb' may I suggest you read a book instead. Oh also, ghosts don't exist, now go play outside.