Digital BW, The Print

I have not followed all the discussions of density changes on the Piezo
list, so maybe some of the Piezo users can help me understand the density
changes I've observed in my Piezo prints.

For some time I printed Piezo using an 1160 with a CIS.  The results were
consistent for quite a while.  I always noticed the green tint, but I
assumed that was normal with the ink.  (I moved away from Piezo mostly due
to my desire for a cooler tone.)

Recently, however, the Piezo inks have become noticeably darker.  I thought
it was the CIS, but when I loaded a cartridge it, too, printed dark.
Specifically, the magenta and yellow position inks appear to be darker than
I used to experience with my CIS.  Moreover, the green tint is less.

So, did the Piezo ink formula change, are ink batches inconsistent, or was
my CIS causing the two lightest inks to print light and green?  The last
option does not seem to be completely consistent with the fact that the CIS
started to print dark also, but that was only after it had sat with little
use for quite a while.

The printer is quite consistent with the MIS inks I've been using.  So, it's
not a function of the printer, like clogged or worn-out heads.

Is this a known syndrome with Piezo ink and/or the CIS?

Paul
http://www.PaulRoark.com