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Calibrating Multiple HP Indigo Presses

  • 1.  Calibrating Multiple HP Indigo Presses

    Posted 05-22-2019 03:25 PM
    I'm calibrating 2 HP Indigo 7900 presses on a Fiery DFE.

    It is the wish of management that we keep things simple, which means not having individual calibrations for each press, but shared queues for the substrates.

    Is anyone running a similar workflow?

    My thought is that I could find passable G7 curve on a specific substrate for both presses by reading in the linear readings from both presses and generating a G7 curve from the averaged data.

    We are not G7 qualifying these presses, but looking to get better matching output from both presses. I would appreciate any advice or help on this subject.

    Any alternative solutions would also be welcome.

    ------------------------------
    Kai Yamada
    G7 Expert
    DCG ONE
    Seattle WA
    ------------------------------


  • 2.  RE: Calibrating Multiple HP Indigo Presses

    Posted 05-23-2019 11:06 PM
    Hi Kai, 

    There is a trade off between simple and quality attainment, and management doesn't often understand this, but we have a procedure that has worked very well for these situations. First a question, do you only need these two presses to match one another, or do they need to match other G7 devices? If only one another then iterating a G7 curve off the default LUT (050, or 075) in your printer is preferred to linear. Once your curve is set up with each press print out a standard test page with images (we can provide for free) and the 3 row Idealliance target (12647-7) and measure it and calculate the ∆E CRF at 95th percentile (E-Factor) of each device to one another, the number should be between 3-7 (think of this as a delta E number for page differences). 

    No matter what the number is, show management the difference between the two printers and ask if it meets their expectations... if it does meet, you know that management expectations are at least the number or higher. If not, then you know their expectations are tighter then what the simple process is capable of. This is an opportunity to help management understand that they need to first define the level of expectations of a color match, and secondly figure out what is the most simplistic process that will attain their desired expectations.

    We can provide you with a trial of free software that will measure color bars, assess G7 compliance, iterate the G7 curve and assess E-Factor Color Conformance.

    This same procedure can be used to determine:
    - How many curves you need for different substrates
    - How many ICC Profiles you need for different substrates
    - How many profiles do you need for multiple printers of same make
    - If you can/should use two different instruments for the same workflow
    - If you can/should use two different viewing booths for the same workflow

    And many more capabilities... feel free to ask me for more information,

    David Hunter
    Your Source for G7 and Color Conformance Solutions
    651.717.0590 Orders 800.91.PILOT



    I'm calibrating 2 HP Indigo 7900 presses on a Fiery DFE.

    It is the wish of management that we keep things simple, which means not having individual calibrations for each press, but shared queues for the substrates.

    Is anyone running a similar workflow? 

    My thought is that I could find passable G7 curve on a specific substrate for both presses by reading in the linear readings from both presses and generating a G7 curve from the averaged data.

    We are not G7 qualifying these presses, but looking to get better matching output from both presses. I would appreciate any advice or help on this subject.

    Any alternative solutions would also be welcome.