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2901- Yellow splotches in gray areas


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Check the diachronic filters in the MLVA lamp house, maybe they are stiff to move or the filters are loose etc.

Try swapping the colorimeter head if you have a spare one, it’s possible it is not reading accurately. Heads from other QSS printers are the same.

Try doing the paper registration/setup again, maybe the data is bad.
If you mainly use lustre paper it may be better to do the paper registration/setup using the 152(2) paper instead of using the 152(1) glossy paper.

Make a service backup of everything before you start, just in case of any problems, you can get back to where you were.

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Are the readings from the colorimeter plausible to the test print?  --  I am guessing "YES" -- when the test print is "blue-ish"  the correction values will be Yellow (+) POSITIVE (ie: Y +3.8); when the test print is "yellow/ brown" the correction values are NEGATIVE (ie: Y -4.0)

It seems like the readings are opposite from each other.  -- yes, they "Flip-Flop'

Does it ever get the print back to neutral? -- Actually, NO, it still doesn't.  Today was a brownish Daily Test print (using Glossy 152(1)), a DIMA() calibration print on GLOSSY (152(1)) was the opposite and a weird bluish color (SEE ATTACHED)--   -- NO.  After daily setup, I print a DIMA calibration print (grey scale and couple of photos with grey border)  and the calibration print will be opposite of the daily setup test print.  I completely forgot that I've been using a different magazine for the DIMA(?) prints on LUSTER (152(1))-- which explains why it isn't "neutral"....   

ex: daily test print is blue-ish, and the  correction values are: +3.9 / +1.0 /  0.0 / +1.2.   Printing the calibration print, it would come out brownish, ie : too much yellow.  So adjust the  balance memory settings in Paper Setup with -3.9 / -1.0 / 0.0 / -1.2, and reprint the calibration print, and it comes out closer to Normal, and then just repeat: print/tweak/print/tweak a few more times until they're somewhat close to neutral.  Then do it all over again the next day. 

If the weekly setup is performed, all the values get mixed up again, and you start from a blank slate and it's even harder to get to neutral.

Print a daily setup print but don't read it.  Shutdown the machine (Power off in close down check F functions) switch it off the breaker switch for 5 mins, then switch it back on and do another daily setup, does the print match the first daily setup?  --  will let you know tomorrow. -- see above post with image attached.

 

IMG-0596.jpg

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Posted (edited)

  

On 3/22/2021 at 1:04 PM, Dave S said:

Check the diachronic filters in the MLVA lamp house, maybe they are stiff to move or the filters are loose etc.

Try swapping the colorimeter head if you have a spare one, it’s possible it is not reading accurately. Heads from other QSS printers are the same.

Try doing the paper registration/setup again, maybe the data is bad.
If you mainly use lustre paper it may be better to do the paper registration/setup using the 152(2) paper instead of using the 152(1) glossy paper.

Make a service backup of everything before you start, just in case of any problems, you can get back to where you were.

Checked the Dichroic filters, a bit dusty and the metal rail they slide on looks like it has /had lubricant which is now all dried up.  The filters' slide is a bit hesitant and re-winds a bit when going from fully open to fully closed and vice-versa -- may be resistance from the motor ?   Should the 3 rails be re-lubricated ?

one of the drive belts is a bit worn right above the gear, but all 3 belts have the same amount of "slack".

 

Have just swapped the colorimeter and will report back in the morning.  Is there any software that needs updating after changing out the colorimeter ?

Will hold off on the paper registration / setup until after results of colorimeter.

Changing to Luster paper for Daily Setup -- I was under the belief that "it's best with glossy".

Also, we've been using (iirc) Evergreen Beauty paper type (135?)  for Fuji Type II Crystal Archive papers.  Which paper type should we be using for that ?

Thanks !

 

Edited by Big Dave
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2 nights ago, we installed a different colorimeter and yesterday morning, the Daily setup was a "tame" : -1.4    +0.5     0.0       0.0

We got the 152mm (6") papers looking amazing in 4 adjustments.

The 279mm (11") papers the Yellow "splotchiness" was back with a vengeance, and couldn't get rid of it, but was NOT there on the 6" papers.....  So bad data ?  

It's strange that it was happening for the 11" but not the 6". so...   Performed Magazine Setup for the 11" Luster paper - test print failed 2 times and accepted the 3rd print (it looked blue like the first print.  test prints were [blue/brown/blue]).

Printed a calibration test print for 11" (to see if greys are neutral) and it's also BLUEAdjusted the Balance Memory settings like for 6", and the yellow splotchiness is gone.

The second morning daily setup was looking more normal but still higher than normal for yellow : +1.4    +0.2    0   +0.1

both 6" and 11" papers were "off" and the Balance Memory had to be adjusted manually again.....

Any other suggestions ?

 

I don't know if this is relevant but in the Daily Setup History, the Dichroic filter Position for "C" is always 400, For "Y" and "M", the "Y" is always > "M".   "Y" is in the range [248 - 300], and "M" in the range [225 - 233].

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Is the CD good?
Because weak CD will have a bigger impact on the 12” paper as there is more paper to develop.

Maybe check the temperature in the CD sub tank matches the main tank, if it doesn’t the circulation may be poor, (blocked pump etc).

Is the CD replenishing properly?

Once you have confirmed everything is good chemistry wise, I would do the initial setup again, to clear out the data. Set all the balance memories back to zero before you do the initial setup.

It seems like the original colorimeter head was over reading.

I don't know about the Dichroic filter Position, I suspect because it never gives a cyan correction, the C filter always stays in the same position.

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Hi Dave, I think you might have found the culprit, but I don't think the CD is weak.   I measured the CD pump output amounts today and it's at 80.5ml / refill  (run pump output measurement 4 times, and divide the total output by 4)    BF = 57.3  and STB = 113.3    (BF and STB values are the same as last time)

AFTER the pandemic quarantine, the CD was a nice syrupy sludge and we had to drain, clean, replace all of it, including the pump, poppet valves & in-line filter.  it was easier / faster to replace the pump than to tear it all apart and cleaning it, and I never bothered to check/adjust the pump output amounts.  DOH!

The OLD pump output amount was 58.3 ml, and it' s been almost 6 months since I did the swap, so if anything, it was OVER replenishing by 21.7ml each time. or around 37% more than required - for 5.5 months.   Could too strong a CD cause the daily test prints to flip-flop like this as well as weak CD ?    and our blacks / dark shadows are not tinted blue. 

FYI, I created a print channel specifically for printing the grey calibration prints that prints to both 11" and 6" luster papers at one time, both 3.5" long ( 88.9mm )  with a matching "kiosk" order, that loads both sizes of prints at once, it's nice.

I'll measure the CD Temps in the morning -- forgot to do it.

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That's strange for the CD rep pump to be outputting so much higher, it should be similar to the BF pump output.
Is the pump identical?

Over or under repping will have the biggest effect on the blue/ yellow, so it could well be the cause.
You will just have to monitor it after calibrating the CD rep pump.

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On 3/26/2021 at 3:50 AM, Dave S said:

Maybe check the temperature in the CD sub tank matches the main tank, if it doesn’t the circulation may be poor, (blocked pump etc).

Is the CD replenishing properly?

Once you have confirmed everything is good chemistry wise, I would do the initial setup again, to clear out the data. Set all the balance memories back to zero before you do the initial setup.

CD Temps (all temps in all tanks) seem to be good.  35.0 in CD & BF to STB with some tiny differences from working tank to the front mini tank with the filter and pump.

Yes, the pump I replaced it with was a reconditioned used pump I had been stockpiling from old machines before they got taken to the dump, so it must have had "something" different for such a big difference in output amount.  I've got lots of pump parts and I just assemble as needed.  It looked "close enough"  If it's too big a difference, I can swap it out with something else.

Thanks.

 

Today, the daily setup was similar to the "new new" of Daily test Yellow being in the +/- 1.x range  (today's Daily Test correction values were: +1.4   +0.2  0.0  +0.2),

The 11" paper didn't need any Balance Memory adjustments at all, but the 6" paper did.  So tomorrow I'll re-register the 6" paper again, and hopefully this "excercise" will be over.

 

Thanks again.

 

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Thank you @Dave S

That was it.  I checked out the Kodak docs for overactive Developer, and added water to dilute the CD, then ran the paper setup / magazine registration and after a few days, the Daily Setup is more "normal", correction values are reasonable again, and seems the issues are gone.   

No more wasting paper....

But the magenta tint is back on the Daily Setup Test Prints.  it's something we've had with this machine since day one.   Basically, the grey, isn't grey, but tinted magenta / red, and Row 14 (of 18) is noticeably more red than (less blue?) those above and below it.  Before we switched out the Drive Voltage PCB we had this issue, after the PCB switch the issue was gone, now it's back with a brand new PCB....  Oh well....

At least no issues in the morning. 

THANKS !!!!!!!!!!!

 

 

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Great news. You're welcome.

Maybe try swapping back to the original colorimeter head to see if that makes any difference.

I would take test print outside to view in the natural daylight and see what it looks like, in most cases I found the print is actually neutral and it is the shop lighting that gives the print a colour tone. Fuji paper seems to be quite sensitive to the light it is viewed under.
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On 4/2/2021 at 11:45 AM, Dave S said:

Maybe try swapping back to the original colorimeter head to see if that makes any difference.

I would take test print outside to view in the natural daylight and see what it looks like, in most cases I found the print is actually neutral and it is the shop lighting that gives the print a colour tone. Fuji paper seems to be quite sensitive to the light it is viewed under.

We are actually using the original colorimeter head now.  When we originally had the Yellow issue, is when I tried swapping the head to the "newer" one (serial # 74xx) in Jan 2019.  Our old one (currently in use) has a serial # 20xx.

I'm comparing the test prints to an actual grey card indoors so.....

I'm going to send you a PM in a few

 

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