Test prints on 7600 have weird midtones


#1

Hi All,
i have a refurbed 7600 that ive got working. sorting through problems with dead channels etc.
now all is good physically. ive inherited an K7 ink set and they have been installed in the correct (i hope positions)
i have topped up shade #5 with a recently purchased bottle. i dont know how old th eother inks are though.
using print-tool on el capitan “no-color management” selecting curve k7-2880-EpEnhancedmatte and printing on ep archival matte (the same paper form what i can tell)
i get the below result which seems to have strange mid tones and much darker highlights than you would expect form the step wedge in the test image. i attach both.
assuming the k7-2880 curve works and fits the paper then i can only thing that one or more of my cartridges is in the wrong place.
perhaps printing an ink separation test chart will tell me which one. thats my next step.
but i just want to see what people thought about the results from the test print.
any thoughts welcome.
yes im very new to it all and gradually working my way through the process.
many thanks in advance for feedback.

ok for some reason it wont let me upload the jpgs so here they are on this link
7 new photos · Album by Christian Hogue


#2

You are at a disadvantage in trying to troubleshoot an old printer with old inks which you are uncertain about for a process that requires exactitude.

From the test target print it is clear (as long as you are following our Gamma 2.20 workflow) that the inks are definitely not sorted correctly.

Where you should start in troubleshooting this is printing the Calibration Mode target in Calibration Mode. That will separate out the 7 ink channels. Visually we can tell a lot about what’s going on from the Calibration Mode printout.

  1. Please print it once with the printer as is. You should see seven distinctly different ink shades. Of course in Calibration mode each shade will print in 21 steps - so look at each of the ink strips and see if they are actually seven different shades of ink printing. Post it here will be helpful.

  2. If several look similar to each other - please remove all of the ink cartridges and shake them gently for about 15 seconds and return them to the printer. Then run 3 POWER CLEANS or initiate the INITIAL INK FILL to move the shaken ink in the cartridge through the ink lines and ink dampers into the print head. Now repeat the Calibration Mode target and see if the system is improved. Please post that picture here.

If you have an Eye1 to measure - you can measure the L value for the 60% patch of each of the 7 ink shades and jot that above each 60% patch when you post the images. We can tell you definitively from that!

If the system is not sound - then you will need to start this printer off with fresh inks. Either your inks are too old, or they have been allowed to print over time without ever shaking and are now too heavily pigmented, or they have been cross filled and therefore contaminated. Ultimately, the inks need to be in peak condition for this process to work!


#3

Thanks Jon,
yes just did the Ink Pattern Mode image print (http://piezography.com/2016/10/02/quadtonerip-ink-seperation-calibration-mode/)
and added it on that link to the album.
definitely problems with shade 6.
the others seem to be visually ok considering the cheap paper im using and fading eyesight.
it didnt say what the example print was done on or what paper to print it on. as it’s uncalibrated i guess it doesn’t matter much apart from how deep the blacks will look.
i will check what ink i have in stock here and if necessary order a fresh bottle form you. already bought 5 and 3 previously. will have the whole set soon! keen to try your Ultra HD once this basic set is going.
many thanks again.
ps i have a color munki also if that helps.


#4

Hi Jon,
ok i’ve uploaded the QTR ink Pattern Test Print AN a nozzle check both as jpgs for easy viewing and as 16bit tifs for closer examination.
we are pretty sure that the cartridges have been agitated and are in the correct place. left to right 1 6 2 4 3 5 7 ie PK LK C M LC LM Y on the 7600
but the nozzle check and test chart shows that SHADE 6 in the LK slot is darker than it should be. and maybe the magenta is lighter than is should be shade 4.
its possible that the epson technician has accidentally swapped the ink lines going into the head while he has been working to clear the lines and get the printer physically working again during its refurb.
it would be great if you could cast your expert eye over the images and let me know what you think. im also happy to send you the physical prints if you need them.
many thanks in advance…


#5

Shades are right but I think what you need is a custom linearization at this point. We have not had an x600 in the R&D lab in many many years.

best,
Walker


#6

[QUOTE=walkerblackwell;13529]Shades are right but I think what you need is a custom linearization at this point. We have not had an x600 in the R&D lab in many many years.

best,
Walker[/QUOTE]

thanks Walter for having a look at those print scans. you saw the piezo document example ink pattern print and my 7600 one. shade 6 or ink 7 looks noticeably different to me. this is an uncalibrated print.
also ive been told that the nozzle check should be dark to light then dark to light again left to right … ink pos 6 seems to break that order. does anyone have a sample 7600 piezo nozzle check to compare with?

from what you say about need to re linearize the profiles then k7 2880 profiles from the community edition for the 7600 no longer match the 7600?
the 7600 with the orginal ink set is no longer supported then?

shall i send you my prints so you can have a closer look with a densitometer? (what address please)
many thanks


#7

Oh, so sorry! You are correct, the piezo sample document was the one I saw. Sorry about that. Blood sugar was low last night, my flub.

It does indeed look like you have settled inks in there (looking at the bottom channel prints). This is evident due to a darkening in the middle of each line and un-even printing towards the right (where it should be darker).

What Jon said earlier holds true. You need to pull the carts shake them, put them back in, and do an initial fill on the printer.

-Walker


#8

No problems! At my age it’s best to double check everything just incase!
I’ll do as you suggest and do another print test.


#9

Dear Christian. I just got a msg from Jon.

The tests you uploaded and the tests you send us by mail looked the same . You are certainly getting pigment settling in your lines. Did you do a shake and several maintenance cleanings and re-print?

best,
Walker


#10

thanks very much Walter!
I had a tech do extensive work including chipping and resettling the carts
and multiple flushes until the system was working freely… So i feel the
cats have had pleny off movement.
The shade 6 ink looks very different though to your original test print.
Have u had a chance to test it with a densitometer to check that its the
correct ink in that slot?
I can undestand hownsettled ink could effect the tones across the ink steps
but not how the whole row could be so radically different.
I can do another agitate and test print in july when Im back from holiday.
Hope your workshops go well.might do onenext year when we have these
printers running properly.


#11

Hi Guys,
im back at the studio.
as i mentioned i will agitate the inks… again. as its been done several times during the refurbing of the printers.

however im still puzzled as to why shade 6, ink 7 or slot 2 on the 7600 looks considerably darker than the one your 7600 test print.
i did send u the physical print so you could do a densitometer reading and discover what ink is in that cartridge because it looks far to dark to be shade 6.

here are the two prints yours and mine side by side below and you can clearly see that shade 6 is definitely a lot darker than it should be.
as firs ti thought maybe two lines had been swapped but there is not another ink channel that seems to be obviously wrong. so ill check that i have shade 6 to fill another cartridge and test it…

meanwhile it would be great if u could test my print and tell me if that is shade 6 or not officially please.
i might oder a whole new 200 ml set to get this 7600 working and do a proof of concept n the whole system before moving on to a 7880 i have waiting to be refurbed as my final printer for piezo.

looking forward to your feedback.

\


#12

Considering the maintenance and shaking etc, it really could just be the wrong ink in there . . .

It looks like you have shade 3 were shade 6 should go . . . or even a combo of shade 3 and 2. Shade 6 would never settle to that level. There isn’t enough to settle down that dark!

-Walker


#13

yes exactly that’s what i thought. is it possible to use your densitometer and tell me for sure which inks are in the stand out slots that seem weird.
shade ink7 channel for sure also i think maybe maybe ink channels 4 and 6 have been swapped (as i said maybe a line has been put in to the head in the wrong position.
ill put what i have of shade 6 left into a fresh cartridge and try it again…

thanks for your thoughts…


#14

due to the rather shifty nature of the old inks, my eyes are just as good as a spectro in this case (aka, not that accurate).

But I would say with high confidence that the only ink that is wrong is #6


#15

OK guess ill order a new bottle of shade 6 asap and see how it goes…


#16

doing a cotton bud sample and swatch of the shade 6 cart and the small amount remaining in my shade 6 inherited bottle they are definitely not matching. i’ve ordered a fresh bottle of shade 6 (there is not much left in my existing one) and will se ehow it goes.

but from your previous comment im assuming most of the other inks need replacing? if so ill order a fullset soon if the new shade 6 looks promising. many thanks again for you practised eye…


#17

I would test with new shade 6 first before ordering a full replacement.
-W


#18

ok the shade 6 bottle has arrived. how should i clean out the current cartridge and put in the shade 6 form the new bottle? ive checked the video tutorials but they all assume an clean empty cartridge. ive seen references to not contaminating the inks with water so not sure the best practise for getting an old cart ready for new ink… thanks


#19

oh found something relevant…

Can I use my existing K7 cartridges with the new Pro ink?
“We suggest that you keep things clean and organized and get new carts. However, if you are on a budget, you can clean the cartridge out very carefully with distilled water (!!!), let it drop out over night, and fill with Pro ink.”

so i guess flush out with distilled water and leave to dry over night…


#20

Any tutorials on how to suck the ink back out of a channel when changing ink carts to minimize waste and contamination? Thanks