Message
Calibration Mode - Weird issue with 10-ink separation image
2017-04-10 by dtrout@...
I'm printing with Piezo Pro inks in my 7900 10-channel printer. The Green channel is mostly dead and that line is loaded with Piezoflush. All the other 9 channels have PiezoPro ink, and print perfectly.
When I print a 10-ink separation image in Calibration Mode, everything looks as expected except in the Orange channel (which has PiezoPro Cool Very Light ink). I'm seeing a really weird "overlay" of ink from the Green channel which prints very light pink in my case since my Green channel is mostly gone.
To illustrate what is happening I made up a modified TIF file of the ink separation image, printed it, then made a quick photo of that which I've uploaded to the files section (CalModeIssue.jpg). On the modified ink separation file I removed everything above the last row which shows the 0-100 density patches for the the Orange channel, then placed a number of test patches of the 100 density ink for the Orange channel at various places on the page.
The page is printed from right to left, i.e. the right edge is loaded pointing down in the printer. That's important to know, because what I'm seeing is that immediately after a patch of the Orange channel ink is printed, the printer is laying down ink from the Green channel. This should obviously NOT be happening. Furthermore, you can see where I placed a solid black line (i.e.a different ink channel) the pink (Green channel) stops.
I first noticed this problem because I saw a very light pink color in the white space between the density patches starting around 55 (you probably can't see the pink in this bad photograph I uploaded). Furthermore, I'm pretty sure that the density of the Green channel overlay is proportional to the density of the Orange channel preceding it, i.e. as you move right to left to the light patches, the pink gradually disappears in between the patches.
Has anyone else seen this kind of issue printing 10-ink separation images in Calibration mode? Not sure if it matters, but I'm running QTR on Windows 10 64-bit. Any ideas appreciated.
Dave