Dead Pixel? Hyperactive Pixel? White Spot? Residual Point Noise (RPN)? CCD Defect?

Pad	You have probably heard all of these "dreaded" terms. Maybe even about your camera. (I hope not) There are several theories as to why these appear. One of them is Cosmic Rays destruction of your CCD image sensors. Another one is heat deterioration of the image sensors. Or even my theory, high incidences of static electricity. There are even theories about airport X-ray machines, and just flying in an airplane.	Pad
	At this time, the major manufacturers of cameras are supporting the Cosmic Ray theory. This means, unfortunately, that if you fly with your camera, that the cosmic rays that are in the upper atmosphere may damage your camera CCDs. Many manufacturers recommend that you ship your camera by truck or boat to any site you will be shooting at. This is probably not practical for many of you. I know you have to be on site at a moment's notice. I feel I should mention here that there is no definitive proof that this Cosmic Ray theory is completely true. Let's just say it's a possibility.
	Now for some better news: Some camera manufacturers have included a pixel drop out or compensation circuit in their cameras. This means that you may have a chance at correcting that spot you see in your viewfinder/picture. Many of the manufacturers will not or cannot confirm the existence of any such circuitry in their cameras. Don't let that discourage you from trying to see if you have it or not. On some cameras activating the black balance will also operate the compensation circuit. You will need to black balance at least once, probably a few more times, or even, on occasion, up to 10 times and maybe that pixel spot will go away. On other cameras there are switches on the prism/ccd assembly that will allow you to activate the circuit. This may get you out of that tight spot where you see the defect and you hope the client doesn't.
	Another possibility, that has worked on various occasion, is to cool your camera down to 40 degrees or less for about 24 hours. (Or if you feel like it, just the image sensor/prism block section.) You don't actually have to freeze the camera, just keep it very cool. If you do this, I recommend that you put your camera in a large plastic bag, and seal it. Put the plastic bag with your camera in it, in your refrigerator, cold garage, or where ever it's cold, for about 24 hours. When you remove it, leave the camera in the bag until it warms to room temperature. We don't want any condensation on it, as moisture on a camera is not good for it. Hopefully that will correct some of your white spot defects. (This has been tried a few times, recently, with very promising results. Though I can't guarantee it will work for everyone).
	There you have it, some hints, suggestions and information on how to deal with pixel defects in your camera. Opposing theories, additional information, or comments are always welcomed. If the information has merit, it will be posted somewhere on this site. I hope some of this information has been of help to you!
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