Micro banding with perfect nozzle checks

7800
9800
9880
7880

#1

I have a new setup with an Epson 9800 running selenium p2 inks, printing with Hahnemuhle Photo Rag Pearl paper. There is microbanding present even though we are getting perfect nozzle checks before printing.

Before installing Piezography inks, we had perfect nozzle checks with Epson ink. We aligned the print head using the printer utility. Then we flushed the printer with Piezoflush and had perfect nozzle checks with Piezoflush. After that we installed the Piezography inks.

We are printing with Print Tool, 1440, Uni-D, roll and sheets. I did an manual Uni-D alignment check already and everything looked good (the best results per channel were on line #5 in all except 1 alignment pattern).

Is there another adjustment to make, perhaps with the media type or paper feed?



#2

I made 2 changes that seemed to resolve the problem:
[ul]
[li]Made a custom paper setting with platen gap set to “Wide”. Previously, it was set to “Wider”. I printed the thickness pattern adjustment on both settings. With “Wider”, none of the lines even overlapped. With “Wide”, we saw overlap and were able to find one that lined up.
[/li][li]Printed at 2880 Uni-D instead of 1440 Uni-D
[/li][/ul]
The initial platen gap change/custom paper type helped, but you could still make out very slight microbanding. I had used the “Wider” setting for years with my other 9800 and 7800 before they were retired. The switch to 2880 seems to make it go away. Will try some more prints and see.


#3

Misfiring nozzles apparently are a cause of micro-banding even when you have what looks like a perfect nozzle check. See here:
http://www.inkjetmall.com/tech/content.php?167-Evaluate-a-Manual-Nozzle-Check-to-Determine-the-Health-of-Your-Printer

But I can’t see any of this in your nozzle check, so unless you can see something that I can’t, then this is unlikely to be the cause in this case.


#4

Thanks Brian for the link - I read through it again. I couldn’t see any blocked or mis-firing nozzles in the manual nozzle check. I also printed an auto nozzle check, which looked perfect as well. Very perplexing. I’m going to hope it’s just a paper feed issue that the custom paper type/platen gap/2880 settings takes care of.


#5

From what I can see, your manual nozzle check looks good with no missing or mis-firing nozzles that would cause your banding problem. I hope your new print settings resolve the issue, so you can get beautiful smooth prints with this machine. There is a big difference in both detail and density between 1440 and 2880dpi, I always print at 2880dpi, but for proofs I use bi-directional speed for faster printing.

Best~ Dana