Hi People, I've been lurking for a couple of months, but I've just ordered a Sprint Scan 4000 from ecost.com and UPS tells me it's scheduled to be delivered on Jan 11. I'm confused about the function of scanning software such as Ed Hamrick's VueScan.
When I expose and develop B&W film, for example, I strive to compress or expand the dynamic range of the subject to best exploit the dynamic range of the film. For a high-contrast subject, I compress by overexposing to bring up the shadows, and by underdeveloping to keep down the highlights. For a low-contrast subject, I expand by underexposing to darken the dark areas, and by overdeveloping to raise the light areas. I have the impression that the scanning software has a similar function between the film and the file. The software permits the user to compress or expand, and to center, the dynamic range of the image on the film to best exploit the dynamic range of the file. For eight-bit color, this dynamic range of the file is 256 levels in each of three channels. If the image on the film is carefully fit to the dynamic range of the file, then that file becomes an optimum archival representation of the image, within the limits imposed by the number of bits per pixel and the number of pixels scanned per inch. Is this correct? But here's my confusion: If the three channels are individually, independently compressed or expanded from film to file, then it seems to me that in general, when the file is viewed, it won't look like the original subject. Image-editing software is then used to produce another file which looks right when viewed on the monitor or when printed. Is this correct? (Ignore, for the purposes of this discussion, any editing to produce special effects). But if carefully scanning the image produces an optimum exploitation of the range of the digital word size, then the edited file is NOT an optimum representation. Are both files saved as archives, (twice as much storage required), or has the process of carefully scanning the image served its purpose, and only the edited file that looks right when viewed is saved? Jack Jansen ---------------------------------------------------------------------------------------- Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
