Working with two printers

qtr
curves
piezography

#1

Hi Dana
I received the new profiles - thank you.
The better one between the two is "K7-SPED-9890-CanRagPto_11-15_pt12.quad” .
What I am trying to achieve is to have two 9890 with special edition ink in them print as similar as possible so we can easily use both of them in our workflow.
our new 9890 prints beautiful with the profile that was made by you but I can not get the same quality and look on our older 9890 with brand new print head.
When looking at the results from both printer it looks like the older 9890 with the new print head has less density and contrast so the print looks muddy , it is also looking warmer .
From your experience Is it possible to bring 2 printers to a very close output ?
I am printing to both printers from the same computer directly from lightroom.
I understand that profiling 2 printers should in theory create two very similar outputs but that is probably only true if the machines are from the same model and the print heads are around the same age , so if two printheads are putting the same amount of ink (same ink) on the same paper and are profiled so linearization and transition between shades is correct the result should be very similar - right ?
Any help will be appreciated
thank you


#2

Hi yl40~

To get two printers of the same model to have matching output with the same ink/paper combination, you will first need to do this:

  1. Print an Ink Separation chart with each printer, on the same paper, with the same settings (2880dpi, 100% ink limit).
    Instructions here: http://www.inkjetmall.com/tech/content.php?144-Print-Ink-Separation-Image-thru-QTR-Calibration-Mode

  2. Dry the prints, and measure the 60% density patch of each ink shade. Compare measurements of the same ink shade between the two prints/printers to determine similarities/differences. If you are unsure about your measurements, let me know what you get and I’ll tell you which are in the correct range vs which may be off.

Let me know your individual ink shade measurements from the two printers, and we will move forward from there to get your two machines matching.

Warmly~ Dana :slight_smile:


#3

Thank you Dana!
Ok, the numbers for printer 2 (the one I am happy with the results) are : 15.56,22.73,40.39,87.26,32.34,63.71,79.51
the numbers for printer 1 are 15.67,23.77,40.37,86.87,30.96,67.51,80.73
I see a big difference in ink 7 (light black) of delta e 3.9 - the big difference in that channel starts at 45% all the way to 100%
can you work with the above numbers or do you need additional information from me ?

thank you very much


#4

Thanks for the numbers! What paper did you print on?
I translated your luminosity measurements to density, and see that your two printers are actually pretty close to each other. The biggest difference in in shade #5, printer #2/good is printing about .061 density darker than printer #1/in question. Other ink shades are exactly the same (#4) to .03 difference (#3).

I recommend using QTR’s Linearization tool to bring the two printers in line with each other.

Warmly~ Dana :slight_smile:


#5

[QUOTE=Dana-IJM;10009]I recommend using QTR’s Linearization tool to bring the two printers in line with each other.[/QUOTE]

If I may be so bold: Relinearising a Piezography Curve (since it’s hard to find detailed instructions on using this tool).


#6

Thank you Dana
I am printing on canson rag photographique. So just to see that I understand your recommendation , you want me to use the cures you made for printer 1 and 2 and create a correction linearization curve on top of them in order to have the 2 printers linearized the same way (the correct way) ?
also, what software should I use to read and save the readings from the spectrophotometer in order for the droplet to read the saved data correctly ?
thank you


#7

And thank you very much Brian_S for the very good information !!!


#8

Do you have a working link to download QTR-Linearize-Quad ?
thanks


#9

It comes included with the latest version of QTR, although you also have to install the curve creation tools. If you’re running the latest version and you didn’t install them then simply reinstall and make sure you select that install option. On Windows it’s located in C:\Program Files (x86)\QuadToneRIP\Eye-One. On a Mac I am reliably advised that it’s just installed like any other application, although perhaps it’s listed under QTR.