New 7890, New p2 system inkset, totally shifted grey values, any ideas?


#1

when I print “21step” calibration file using Meth3 1_6 quad file, I get densitometer reading of 0.18 for blank base, and 3.13 for 100% and 1.71 for 75% grey!
It looks shifted all the way. i can get it to be semi normal by creating a compensation curve in Photoshop. but I thought manual says I suppose to get “perfect” linearized printout by using correct media, correct ink, correct “canned” profile. Well, media is Pictorico pro ohp, ink is your P2 system on 7890 and file is “21Step” and software is “PrintTool” on a mac running 10.6.8
I really cannot see where it fails.

Thank you,
Sergey


#2

I will try and help you. What do you mean by shifted all the way? If you were to make a smooth grayscale ramp, (not a step ramp), does it appear smooth on the film? Or are you expecting it to behave in some way that it is not? For example, are you expecting to measure 1.0 linearization \ and clear film base? It doesn’t work that way.

But if the smooth gray ramp is not smooth - then you may be using the wrong generation of curves for your ink positions or your ink positions are not correctly installed or you are not adhering to the Gamma 2.20 workflow or some combination of these or other issues. Certainly an optical density of >3.0 indicates that black ink is printing and there should be no black ink printing with the Meth 3 curve if the inks are in the correct order. Clear film base should print with density to imitate film base + fog in meth 3.

Can you confirm your shades per color positions for each color position for me?
Please confirm the exact name of the curve you are using.
Have you looked at a smooth gray ramp yet - is it smooth or lumpy?


#3

The ramp is smooth, it is the density that appears to be excessive. I was trying to post a photo of 8 ink calibration target but forum would not take the file (jpg, rgb, 8bit) I printed 21step file that comes with Quadrone rip, did not change the file, printed with Meth3 1-6 profile on best Pictorico. I can use my xrite density meter to measure 65% spot in all ink printouts on a target file print…


#4

If the ramp is smooth - then the negative may be working perfectly.

Did you measure dMax on film by Uv or Optical?


#5

The problem is, I need to output both positives for my copper plate photogravure process and negatives for platinum. I have not run platinum yet, waiting to resolve ink densities issue. For my positives I need a dmax range of no more than 1.6, what is the range for negatives for platinum that you would recommend? I can play with photoshop curves to adjust files for my process, but I need to be sure “neutral” workflow gives me intended linearization. I run come color inkjet on 7880, no problem, works great, I run Quadtone using just three shades of grey on 7880 with my own quarter profile, works great, wanted to Upp the quality, bought new 7890 and new set of P2 ink, and here is the snub. I do have OEM photo black cartridge installed in fifth position, but it should not be used by meth3 profile, right?


#6

I measured film by optical on my old xrite 810


#7

I started using Cone Studio Piezography System back in 2001, on Epson 7000, and it was a great experience, migrated thru several ink sets, now trying to get really good quality for my photogravure and platinum processes… I am sure this will be resolved and I will be in heaven… Until 7890 clogs… I understand design is not as stable as old 7880


#8

Then something is probably wrong in your workflow. it is not possible to attain optical density of 3.3 without using black ink. Methodology 3 curves only use shades 2 and higher…

Of course the negative can be perfect and your x-rite is not.

Platinum / Palladium has a density range maximum of about 1.70 - really it is very hard to exceed this without going into triple coating etc… so the 1.7 curve would be correct. You can find your optimum exposure using a step wedge exposure over the unprinted Pictorio Ultra Premium OHP film. when you arrive at the optimum exposure - you can then print out a 21 step or just a 100% gray patch using each of the 1.4, 1.5, 1.6, 1.7 and 1.8 curves. Align these Ultra Premium films next to each other and cover the edge with an opaque card and expose with optimum exposure time. The patch that produces specular white or just a slight tone (if you prefer) is the correct curve to use with Pt/Pd.

Of course there are many many different possibilities of contrast through chemistry and paper. No matte what combination you use. You should standardize it. Then use Photoshop to make a correction curve. We can supply you with a suggested one. But really this is personal taste or you can follow the tastes of PDN and use it to arrive at a correction. After that - each neg you produce will print correctly for that chemistry with some exception to humidity of course.

For photogravure the Density Range is really rather narrow. First it needs more density in dMin and then not very much density in dMax. I am probably not telling you anything you do not already know. So the 1.4 will be necessary and you will probably sill need to further limit the output using the output levels limits… When I was making aquatint photogravures I remember my dMin about 0.24 and dMax about 1.4 - But it was more than 20 years ago since we stopped making gravure plates for photographers. However, the sensitivity of the carbon tissue is not better than then. You can try and produce a same exposure and DR testing on your end. I am not familiar with the contrast correction required. But I do not believe that dichromate is as peculiar as the oxalate. So the correction curve should be much more benign.

Hope this makes sense?


#9

[QUOTE=zsilver;10181]I started using Cone Studio Piezography System back in 2001, on Epson 7000, and it was a great experience, migrated thru several ink sets, now trying to get really good quality for my photogravure and platinum processes… I am sure this will be resolved and I will be in heaven… Until 7890 clogs… I understand design is not as stable as old 7880[/QUOTE]

The 7890, 7900, 9890, 9900, P6000, P7000, P8000, P9000 print heads are like delicate daisies compared to the 7880. Of course the new P6000, P7000, P8000, P9000 printers will disable themselves when they detect non-OEM carts. So, they are not in the equation moving forward if you wish to experiment. I would look instead at good refurbished 7880 printers. They are five year printers. A 7890 is a 1-2 year printer. Of course some get 2-4 years from a 7900 but its rare. And at the same time some get 7-8 years from a 7880 - yet that is not as rare. The cost of a new print head for a 7890 can buy you a refurbished 7880.

Of course you can get another 7890 for free from someone who used it for color and has a permanently clogged nozzle. Useless to them - valuable to you. Our customers are getting free Epson ink printers and then we are converting and mapping out the bad channels for conversion to Piezography.

So? Good times and bad…


#10

You are absolutely right about traditional copper photogravure, I practice it constantly and from my experience to have smooth etching I need some density in highlights of at least 10% grey and open up shadows for detail not to exceed 85%, that is relative to “normal” output of 1.6 or 1.4 dmax.
I will measure densities of every ink position at 65% -I print calibration file at 100% ink and dark ones are falling to flat black pretty soon.
I ca mail you all the printouts, my confusion also comes from the fact that I have 9 ink cartridges installed, with OEM photo black in 5 position, but it should go unused, right? So my 8 ink calibration file skips it?


#11

About a year ago, when I was installing this inmate in a new printer, I did not have anything for 5 position,the been advised to put something in there, not to have it empty, bought and installed regular Epson photo black cartridge, and vagley remember hitting "load Matt black " button on printer panel. Could I have done something wrong and now printer draws ink from OEM photo black instead of cone Matt black?


#12

So, finding correct exposure for platinum, I can use standard stouffer strip film, put over unprinted Pictorico and expose with different timings, and then see which one gives white precisely at 0% or 5% on a scale, right?


#13

Sorry, I forgot I will be using positive scale… So, I will find a patch on stoffer with 1.7 reading and see where it produces white on paper?


#14

can you relay to me what are your ink shades by color position.

your printer has only 8 ink channels but 9 inks
the black head can only print one of the two black inks at one time.
so if you are in MK mode then only MK ink prints
to see PK you need to put our printer into PK mode


#15

I will measure 8 ink calibration printout… Should I measure at 65% patch? I will double check but pretty sure printer lcd panel says “mat black installed” . While printing, in QTone panel on the bottom there are three choices - “black ink installed”, “photo black” and " mat black" Do I need to choose any specific one while sending file to print?


#16

you either need to stay analogue and use the stouffer or go digital and use the Piezography film for testing.

But you can do it any way you wish to as long as you get there. I can tell you what I do with Pt/Pd printing and if you want to use the system the way I do, you can. If you want to use the system the way you want to use it you can. Whatever gets you there is all that is important.

This is my workflow for pt/pd.

  1. I standardize my chemistry. Contrast is NOT achieved by moving chemistry when making digital negatives. Rather contrast is altered with Lightroom or Photoshop.

  2. I find my optimum Density Range in two steps.

a) using a sheet of unprinted Pictorico Ultra Premium OHP film I generate a step wedge of accumulative exposures to determine [B]optimum exposure[/B] to make black on a chemistry / paper combination.

b) I print a square of 100% density onto Pictorico Ultra Premium OHP film using each of the 5 Piezography curves and expose them simultaneously with the [B]optimum exposure[/B] to determine which curve produces “white”. I use an opaque card over the edge of these black squares to make determination of “white” easier by preventing the pt/pd black to surround the white patches in the final print. That curve which produces the white I prefer is the curve that is used for all further negative making for that chemistry / paper combination.

  1. I use Photoshop to adjust the contrast of the image via curve that is suitable to my desire for tonal latitude or use the Curves Calculator II or III to impart it’s aesthetic. But, I prefer to use my own. We can supply you with a “starting point” photoshop curve. If you change your chemistry which changes the contrast in the final print - you need repeat this process. But I do find that the emulsion if left standardized seems to use the same optimum exposure and QTR curve. Usually 1.70 or 1.80 is the best curve for Pt/Pd. I think that Curves Calculator when used for the Photoshop curves opens the deep end too much and lowers the lights too dark. So I prefer to make my own.

hope this helps


#17

no black ink is ever printed with methodology 3 so it is irrelevant if you have MK or PK or simply a flush cartridge installed. The Methodology 3 curves only print from shades 2, 2.5, 3, 4.5 and 5.


#18

[QUOTE=zsilver;10186]So, finding correct exposure for platinum, I can use standard stouffer strip film, put over unprinted Pictorico and expose with different timings, and then see which one gives white precisely at 0% or 5% on a scale, right?[/QUOTE]

i do not use analogue tools for digital negatives.
i make my own step exposures using printed film from the Piezography Digital Negative system.
if you can correlate with a Stouffer strip then by all means produce the results you are after any way you prefer.


#19

[QUOTE=zsilver;10187]Sorry, I forgot I will be using positive scale… So, I will find a patch on stoffer with 1.7 reading and see where it produces white on paper?[/QUOTE]

again - i would generate the exposure and DR via printed film rather than relying on a Stouffer. But if you can correlate the two systems - then it does to matter how you arrive at the results you want.


#20

Thank you so much Jon! It helps a lot. I am deal with and calibrate my photogravure process, but I am new to platinum. Once I will get it going, I am sure will want to venture into two or three layers “duotone” and tritone exposure layering in platinum, but for registration I will need to mount it on aluminum. I understand the unit I will need to procure, for hot vacuum mounting, but specific adhesive sheet manufacture USA mystery , the one that will allow me to safely uountcpiece after all is done. Do you have any information about that? It would be greatly appreciated…