strange 'banding' or streaks on my 9890

[neilwill]

Was wondering if anyone had any ideas about this?

I am getting strange 'banding' or stripes in the black areas of my prints?

This is on my less-then-a-year old Epson 9890, using OEM inks, printing on Epson Hot Press, is happening on both the Bright and Natural versions of the paper.

I put the word 'banding' in inverted commas, because I'm not sure if that is the correct technical term for the problem? In my experience, banding, as caused by a clogged or defected nozzle, is a thin straight line, parallel to print head direction, running across the print. This issue is wider, softer, faint repeated stripe that seems to occur near the edge of the print. The stripes do run horizontal, in the direction of the print head but seem to occur in areas or groups, don't run across the whole print, if that makes sense.

I am attached pictures below which will hopefully better illustrate the problem.

Seem to occur on the edge of the print furthest away from print head 'parking station' (i.e. end furthest away from pump cap assembly). Is it possible problem is related to air pressure in the ink deliver system? That as the print head moves to the end of its pass, the ink pressure drops?

Or is it possibly feed related?   

Any comments or suggestions would be gratefully received

Many thanks
Neil

[Paul2660]

I am assuming you have a totally clean nozzle check and don't have any deflections? 

How wide is the paper, 36" or 44"  If you take a 6" x 30" or 6" x 40" test strip of total 100% black and print it, do you see this only at the far end, away from the end where the head is stored? or do you see it to some degree across the entire print? 

For this matte paper, which is a 300 weight, you might also need to adjust the platen gap.  If you have it on widest, back in down to wide.  Also double check your media settings, not sure what Epson recommend for this paper, I would start with WCRW but try some other media settings and platen gap settings to see if you can get a better combination. 

If you don't have anything showing on the nozzle check, either a deflection or missing band, then the head is fine and this may be an alignment issue.  The 9890 should run an auto alignment process every once and a while, however you might need to re-align the head. 

You are still under base warranty, so that's a good thing. 

Paul

[Chris233]

Hi Neil,

a couple questions to better understand

Can you post a pic of the nozzle check before the print starts and after the print completes? No cleanings between them.

When the room is quiet, do you notice a change in the sound of the carriage assembly as the print head makes the full pass? Possibly could be a dry area on the rails vibrating the carriage (print head).

The first print looks like the banding is wavy, which could reflect wavy media or a defect...could you cut a sheet, rotate, and run a test print with the media loaded in the opposite direction? Or same test print with different media.

When you measure the left and right vertical edges of the print, are they both exactly the same length? Assuming the print is a rectangle.

[JRSmit]

Neil, can you elaborate more on how you print: what are the printer settings used?

[darlingm]

Is high speed mode in your driver on?  If so, try turning it off.  My 9900 (and some other people's) shows banding in pure-black or near-pure-black areas like yours on certain media (but not all) if high speed mode is on.

[Paul2660]

Is high speed mode in your driver on?  If so, try turning it off.  My 9900 (and some other people's) shows banding in pure-black or near-pure-black areas like yours on certain media (but not all) if high speed mode is on.

+1. Good point I forgot about this.

Paul

[neilwill]

Thanks for all the feedback and suggestions and apologies for delay in responding from my side. Been swamped with other work.

Have just now had a chance to try some experiments with various options

To try and answer some of the questions......

Yes nozzle check appears flawless before and after printing, even under close scrutiny with a loupe
I have listening very closely and unable to detect any change in sound as carriage travels back and forth, sounds quiet and smooth to me.
The banding appears on different media. Have tried on epson papers Hot Press Natural, Hot Press Bright and Watercolour Radiant White with apparently little difference.
Interestingly, one (but not both) of the full size (100x100cm) tests I just did on WCRW was out of square by 2 mm. The right hand vertical side of printed image was 2mm longer then the left hand side?
Adjusting platen gap appeared to make no difference
Turning High Speed on and off appeared to make no difference.

I am printing from PS, on a Mac, using Epson driver.
Use the appropriate downloaded profile (i.e. WCRW for WCRW etc) printing at 1440, microweave on.

The banding looks 'wavy' to me, almost as if the paper is not flat at time of print head pass? Could it be something with suction fans not working properly?

Anyway, have finally managed to get local Epson dealer to commit to send technician out tomorrow, (after about 10 days). Machine is still under 1 year warranty. Generally technicians out here in South Africa pretty useless, if it's not in the manual they're usually stumped. Holding thumbs none the less.

Thanks again for all the responses, will report progress
Neil     

[Paul2660]

The 2mm difference is skew error. If it's on running length if the print (which ever part of the print follows the paper as it flows through the printer). The width should always be 100% accurate.

Skew is an issue I have had with all the Epson's I have used some much woes than others.

My last 9880 was as much as 1/4 of an inch before Epson replaced it or actually let me trade it towards a 9900.

Paul

[jferrari]

Neil, just for giggles turn up the ink density by 5 to 10%. That worked for me for a similar symptom.    - Jim

[Cornelius]

I just found this topic and was wondering if the Epson technician could resolve the issue with the faint banding?

My 9890 has exact the same issue. I tested two different matte fine art papers (Tecco PFR295 and Tecco PFR220) and with the official driver settings from Tecco I see the faint banding in solid black regions.
Nozzle check is perfect and I see it only in the blacks. Tried already an ink purge pattern for all colors to check and it is definitely only in the blacks.

[Cornelius]

So at least for the Tecco PFR295 FineArt Rag I could resolve the problem. The driver settings are extremly crucial here.

Tecco tells, if using their ICC profiles use the following:
Enhanced matte paper
thickness 3
ink density - no adjustment

Finally I found out, that I used "Archival matte" paper. So I changed this but still had the banding. Then I added Super MicroWeave and the banding was gone. Solid perfect black prints.
I also tried UltraSmoothFineArt Paper and Textured FineArt Paper in the driver settings including the Super MicroWeave. With both I had no banding but the colors changed. I'm not sure why, because I still used the ICC profile for the PFR295 paper.
So for me it seems that the paper settings, even if you your own ICC profil has a quite strong influence in the colors. Any ideas why?