Thank you very much Alfred for the detailed and very helpful reply. I am not sure I understand your explanation, but if I understood you right the camera's firmware is designed in such a manner as to compensate for a certain number of dead pixels so that they don't show in the final image. Since the firmware is universal and developed for all cameras, instead of a specific one for every camera that leaves the production line, I have to assume that the calibration you refer to is what is going to compensate for variations in the location of dead pixels from one camera to another of the same model since they will likely have dead pixels located in different spots. When you say "multiple shots of dark frames" what type of subject should I photograph ? You say that these dark frames should be e-mailed to the technical support department of Canon, but judging by the type of assistance I received from them over the phone I honestly doubt they would be able and/or willing to provide this type of analysis of my camera's sensor. Outside of sending the images to Canon's tech support, is there another way to test these dark frames and verify if the calibration has been done properly ? Is there a web site that describes this entire process in detail including how firmware and calibration are supposed to compensate and/or suppress the presence of dead pixels ? I have asked Karl a question about a way to try to locate dead pixels in my post replying to his. I would greatly appreciated it if you could read that post and tell me what you think about that idea and how that could be made to work. Thank you once again for your detailed and very helpful reply. I appreciate you and all other posters taking the time to help me with this issue. Best regards, Joseph --- Dr. Joseph Chamberlain Oral and Maxillofacial Surgery ---------------------------------------------------------------------------- On 10/24/05 10:44 PM, "Alfred Tay" <alfred_tay@xxxxxxxxxxx> wrote: > Joseph, > > Shoot multiple dark frames of the CCD. Overlay them and you can see if what > White Bad Pixels counts are. If possible use RAW images that have not gone > throught the image pipeline. There are acceptable limits of WBPs and they > are calibrated and compensated through these darkframes. SO these WBPs > should nto be seen in the final images if the proper calibration has been > done and compensated for in the Firmware. > > I would suggest that u email these darkframes to the TECH support and make > noise until they give u a satisfactory answer as to what the limits are. > > Hope this helps > > Alfred > > _________________________________________________________________ > Find just what you are after with the more precise, more powerful new MSN > Search. http://search.msn.com.sg/ Try it now. >
