Mark² said:
I still challenge anyone to produce evidence that ANY media will show the
useful exhibition of 9600dpi from an ink jet type printer.
The dpis aren't there because someone might actually see
the resolution, they are there because the inkjet dot
is not a '24-bit' dot. The printer has to dither - and the
more dpi, the better it can do this.
So you have to divide the stated dpi by the number of inks
and then further by number of 'levels' you want to have
from one ink (depending on whether the inkjet can modulate
the size of the dot or not this really matters or not).
A 5760x1440 dpi printer with 8 inks is in reality 720x1440
for one ink color. Divide the 720 by two and you get 360 lpi -
something that is not far away from what one can see with
bare eye.
My previous printer was a several years old 1200x2400 3-ink
dpi HP all-in-one. The photos from it were good enough for
a 8 x 11 print that you don't look at closely, but were
unacceptable for regular 4 x 6 in - the dithering was clearly
visible when holding from a normal viewing distance.
My current photo-printer is a 5760x1440 Epson R1800 and
it is fantastic. I think one could construct an example
that makes its limits visible, but for normal use it
is amazingly good.