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In article <7B2FF2DC-77AB-11D6-842E-0003931C4CFA@mac.com>, Peter Tattersall <email@example.com> writes > >On Tuesday, June 4, 2002, at 12:03 AM, SKID Photography wrote: > >> Peter , >> I don't think you'd get a moiré pattern with an Epson printer (and >>driver), no >> matter what the file resolution is, as the ink dot pattern is >>stochastic and not >> in a grid, whereas the pixels are in a grid....The ink pattern is >>very similar >> to the grain pattern on film, which is to say random. > >Easy enough to check. Sometime in the next couple of days I'll build an >image contrived to generate moiré patterns and I'll report on the >results via a C80. The inking may be stochastic, but there is still an >underlying grid - otherwise you could never get a nozzle check with >straight lines. That said, I think it will take a _very_ contrived >image to force a moiré pattern with the current drivers. > Its easy to create synthetic pattern that will alias and produce moire patterns - it was analysis of such alias patterns that determined that resampling was occurring and what the resolution of that resampling was. Try printing a series of black and white lines one pixel wide and one pixel apart at around 725ppi - you get a pattern of 5 lines per inch on the paper, because the difference between the 725ppi and the resampling resolution is 5ppi. But getting something like that actually occurring over a significant area of a real photograph is unlikely, to say the least. -- Kennedy Yes, Socrates himself is particularly missed; A lovely little thinker, but a bugger when he's pissed. Python Philosophers - Turn off HTML mail features. Keep quoted material short. Use accurate subject lines. http://www.leben.com/lists for list instructions.