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>Unlike many young thinking people today, not everything "old school" is bad or >wrong. However, please help me understand what you mean by your statement, >while the data is in its analog state". Other than exposure and focus, how are >any image elements edited before they are converted to bits? Unless there are >some manipulations that I am unaware of (which is entirely possible), the >scanner software peforms its operations after the scan. Mind you, it my seem >ike tey're being performed during the scan, but what happens is the scanner >scans some data, manipulations are performed, then it scans some more, the new >data is manipulated, then again, and agian, until the entire frame is scanned. Mike - It sounds to me like the above scan scenario is referencing a typical flatbed scanner. Setting up a high end scanner, say the Hell 3000 series of drum scanners, the image that is taped to the drum, be it transparent or reflected, is adjusted for hi-light, shadow, mid-tone, quarter-tone, and three quarter-tone. Global and selective color adjustments can be set-up if desired. Under color removal and unsharp masking is determined. Scan size,resolution, and of course focus is set. Most of these adjustments are determined by digital readouts on the scanner from measurements taken directly off the original image that is about to be scanned. When the drum spins the image is scanned by a light beam. The above setup paramaters are taken into account and measured against the scanners LUT's. The reflected or transmited light is passed thrrough RGB filters, broken into components of RGB light energy and amplified further by being passed through RGB photomultiplie tubes. So far the data is still in an analog state and the scanner adjustments that were set up for that image are being applied in that analog state. But after the Analog to Digital conversion(after passing through photomultiplier tubes), then the data becomes digital, of course. Thus, adjustments, or data manipulation, to the scanned image took place in an analog state, before the digital data was passed off to a disk, workstation, or whatever. One could simply set hi-light, shadow, and focus at the scanner and send that raw digital data to the workstation for final image editing. That is o.k., and can work, but it is not the best route for optimal results,IMHO. I have been experimenting with scanning that way but passing the raw data through the scanners profile at the work station,converting to CMYK (in this case I am aiming for a printing press), and making whatever tweeks I feel necessary. I am seeing some advantages to this (primarily the ability to scan a lot of material without laboring over individual image set-ups - relying on the profile to do most of the work), but the one caveat so far is possibly the black channel. Does the scanner profile really give me what I want, or amI better of setting that up in the scanner ? I am just not sure about that yet. For ink on paper via offset printing the black channel is important. Anyway, I hope this rather long winded reply helps answer your question. Fletcher - Turn off HTML mail features. Keep quoted material short. Use accurate subject lines. http://www.leben.com/lists for list instructions.
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