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If you don't mind, I'd like to advance this matter further. Some optical 2400-2800 dpi scanners don't seem to have this problem to any degree. Is it possible that is due to their having poor enough optics to "neutralize" this aliasing by actually scanning well below the 2400 dpi "minimum"? As an example, I noticed a lot of other problems with the HP S-10 and S-20 scanners, but not those discussed below. Even the Canon FS 2710 has considerably less of these specific problems. I have heard from one source that the true resolution of the S-10 was only about 1000 dpi due to optical path issues. The Nikons also might be more vulnerable to exaggerated grain due to the nature of the light source, which is pretty unforgiving, while the Minolta use a diffused cold cathode type. Can sharpening take place in electronic circuit design, as it can, via filters, in effect with audio signals? Art Kennedy McEwen wrote: > In article <3C99CC25.firstname.lastname@example.org>, Arthur Entlich > <email@example.com> writes > >> Kennedy, >> >> Your explanation sounds feasible, except for one thing. The Minolta >> Dual II and the Elite II both also suffer from this problem >> (exaggerated dirt dust and grain) and they are both optically 2820 x >> 2820. >> >> Now, if you are saying it due to this resolution range, that could >> explain it, since I recall some discussion around the possibility that >> scanners in the 2400-2800 dpi range suffer from grain aliasing due to >> the frequency of the grain relative to the 35mm frame size. >> > That is exactly what I am suggesting Art - interpolation doesn't change > aliased artifacts, the issue is the limited resolution. Even the > earlier Nikon scanners (such as the one I still have) suffer horridly > from grain aliasing due to the limited resolution of 2700ppi. > >> Otherwise, I still wonder if the problem isn't "hidden sharpening". >> > There may be other reasons, indeed (not having actually seen any of the > images that David is concerned about) I could be way off base here, but > his description of the issue has all the hallmarks of grain aliasing. - Turn off HTML mail features. Keep quoted material short. Use accurate subject lines. http://www.leben.com/lists for list instructions.