I read Giorgio's latest post in the 3800 diary with interest. Thanks for doing the test!

One thing to note is that the test is about color. It's good to hear that the colors are very close between the 4 variations.

My personal experience (with my 3800 which arrived three days ago) is that differences in tonal smoothness and dithering between 1440/2880/unidirectional/bidirectional printing are hard to see with a profiling target. The reason is all you see are solid color patches.

For synthetic targets, it's better to use a "blends" target such as the one on Bill Atkinson's site, which is normally used to check for driver issues when trying to arrive at optimal printer driver settings. This sort of target shows you smooth color transitions between many different colors.

The results also depend somewhat on the type of paper. For example, with Premium Luster it is quite difficult to see meaningful differences between 1440 and 2880 dpi unidirectional, but it is quite apparent on Moab Kokopelli Studio Semi-Gloss. The Semi-Gloss is a smoother surface than most luster papers and thus may show dithering differences more. Even with Premium Luster, though, I was able to see that tonal transitions in 1440 bidirectional were definitely roughter than 2880 unidirectional.

Just FYI.

Eric
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Hi Eric,
your concerns (and suggestion) are very true.
I have the same concerns and I made it clear in my text, that ...
"Please keep in mind that my conclusions, so far, are based only on color Testcharts and measurement files. I have yet to compare two "real life" images to see if there is some subtle difference that might have escaped the numerical probing of the spectrophotometer."

I plan to extend my comparison soon and I'll report my findings.
Thanks for the feedback.

Giorgio Trucco

Giorgio, thanks for updating your test and notes. Can you please tell us which paper you used? Was it Ilford Smooth Pearl again?

I'm very encouraged by what you report, but on the other hand I'm a little concerned because I can see the differences pretty clearly between 1440 uni vs 2880 uni on some papers. On Premium Luster (similar to ISP) I can't really, but on others I can ... so I'm wondering if this is more of a paper-dependent thing, or if something funny is going on with my 3800.

Thanks,
Eric
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