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In article <firstname.lastname@example.org>, Tom Sawyer <email@example.com> writes >This is a great thread you folks have started as its starting to take >some of the mystery out of the Epson printing process. Am I correct >that the printer puts one of the six inks in one spot on the page? I.E. >all non-CcYMmK colors are actually dithered (Saurat lives)? > Yes, they are all dithered unless the tone exactly matches the colour of one of the inks. However, the dither algorithm used (and if you run a patent search you will find details of over two dozen patents that Epson has on the process) is similar in concept to that of a delta-sigma analogue to digital convertor where the quantisation noise is distributed equally across the page rather than maintained within a single "dither cell", as is often the case. Consequently the full resolution of the image (up to the resampling limit) can be retained enabling the finest detail to be reproduced while the tonal error is distributed over a larger area, making it almost imperceptible. >Rumors of earlier discussions passed on to me could be summarized as >"any image resolution of density higher than 240ppi has no affect on >the printed image". That's certainly a rumour - and it's certainly wrong for any recent Epson printer. Try a detailed print at 480ppi and then downsample the data to 240ppi and print again. If the printer couldn't cope with more than 240ppi then the 480ppi print would not have any more detail - but it does, although you may need a magnifier to see it. Average human eye resolution is around 250ppi at a 10" viewing distance, so your eyesight could be nominally perfect according to the optician but you might not see the difference that another person will. -- 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.