Hi Jack, > Okay Austin, I've got the Doctor looking over my shoulder right > now. He says > that with MOST scanners (especially ccd) because of the pixels sensor > density, there is light piping between sensors causing a loss of > sharpness.
I don't believe it's light piping, but electronic crosstalk between adjacent sensors, which is very dependant on color (red is worst, blue second worst and green the best). If it was lightpiping, I would think it would be the same across all three colors. Please run that buy the Dr. > He is > telling me > that a drum scanner is an exception because it masks the light going into > and out of the film. Now that is interesting. I understand the principle, but my experience, is that drum scanners actually require more sharpening than high end CCDs...at least that's what I've seen in scans I've done on both a Howtek 4500 and a Leaf 45. Though I agree, what you say makes sense theoretically. I do agree that the color smearing isn't an issue with PMTs, as it is with CCDs, simply because PMTs only "read" one pixel at a time, and therefore there is no possibility of this type of crosstalk. > Does this help? I wanted to see if you had some other answer than I had. I don't know that I believe the lightpipe issue...we've always attributed it to what I stated. If you (or anyone for that matter) or the Dr. have actually done experimentation that shows it is lightpiping...I would like to know. Since I have not done any actual sensor design, I just use them, I have not done any of this, but it would be interesting to know. Regards, Austin ---------------------------------------------------------------------------------------- Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body