Digital BW, The Print

The Luminous-Landscape review of Piezo printing stated that
the Piezo prints show more detail than the Epson driver prints.
It claimed that the Epson driver cannot take an input file of
more than 360 DPI. Feed it a higher resolution file and the data is
discarded by the driver.

Either my 1160 and Epson driver are very unusual, or this is one of those
urban myths.  In the Files>Message Related Files section of this forum I
have put a resolution test that shows that at least on my 1160 the Epson
driver does take advantage of information beyond the 360 dpi alleged limit,
and the Epson driver print very arguably is sharper than the Piezo print.

(The Files section is at the following URL:
 http://groups.yahoo.com/group/DigitalBlackandWhiteThePrint/files/ .
Then go to the "Message Related Files" and see the "Piezo-Epson Resolution
Test.jpg" file.)

The limit of a 360 file is 7.2 lp/mm; the limit of a 720 file is 14.4 lp/mm.
These are what one gets with alternating one-pixel-wide black and white
lines in the respective files.  The test file I printed with both the Epson
driver and the Piezo driver was a 720 dpi resolution file with resolution
targets going up to the 14.4 lp/mm limit.  The file was printed with the
same 1160 after the heads were aligned.  LPM paper was used.

The print was then scanned at 1200 dpi.  No sharpening was done.  Some jpeg
artifacts are apparent, but the image shows the same basic information as
the original tiff file.

Because the Epson driver print shows some (limited) ability to resolve the
14.4 lp/mm target, it is clearly not throwing out information above the 360
dpi level.  At the 360 dpi level there would be no separation of the 14.4
lp/mm lines at all.  (By the way, my standard file resolution is 360 dpi
because it can readily resolve 7.2 lp/mm, which is more than the
generally-accepted 5 lp/mm limit of the human eye.  The comparison prints
I've done at 360 and 720 have at most what I would call a barely detectable
difference.  It's not worth the extra file size.)

Take a look at the resolution test file print and draw your own conclusions.

Maybe someone else has a system that reacts differently, but on my 1160
Piezo is simply not sharper than Epson.

Paul
http://www.PaulRoark.com