Consistency and Uniformity

Discussion in 'Canon imagePRESS Digital Presses' started by billy, Nov 11, 2007.

  1. billy

    billy Member

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    Hi to All,
    Anyone knows how Good is the Imagepress (C1 and C7000Vp) in Terms of Consistency and Uniformity? This one Good question when buying a digital rinter.
     
  2. kessai

    kessai Member

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    Billy, from my experience it is pretty good. Most solid colours are fine though I find grey is on the weak side. Still more to try on T1. You are not running one right now?
     
  3. billy

    billy Member

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    Hi kessai,

    We have the C7000vp. As I made some preliminary testing after calibration from engine and software, the uniformity seems to be not very good accros the print.I am having a a difference Delata E of 1.8. The delta E between 1 and 100 is already 6.0 on the grey and green side. If I am going to use the Delta E 94, bigger color difference I get. The delta E of 2 they are talking, to me that is in between pages. but not fom first to last. Worst what my friend got with his C1 after changing The Corona wire, it looks like a vignette, left side is good density, right side has 0.6 density. After Q1 calibration, still a difference of 1.2 D.:confused:. There was no explanation from the Engineers, well I am not suprised since they do not know what what delta E means. It looks like they are not knowledgeable about color, more when I ask if they know about Graphic application like Adobe and Quarck.
     
  4. etep571190

    etep571190 Member

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    Hi,
    To me Consistency and Uniformity mean two different things. Consistency, does page 1 look like page 100 or 1000 and so on. In that regard the c1 and 7000 are Canons best yet. I know the are better than many other manufactures copiers. But then again I haven't seen every copier out there. As far as Uniformity, even distribution of toner across the page. Have you done Shading Correction? Both machines have this option. I should balance the 4 colors separately across the page. I have seen it work wonders. It can be done visually, with a densitometer, or through the rip with a spectrometer. Spectrometer works best. Doing a color cal on the rip would not correct uniformity issues. Different but not correct. I don't know a lot about delta e but as I understand it the C1 should have a lower delta e.
     
  5. billy

    billy Member

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    Hi etep,
    Weve done shading and densitometer correction using X-rite's Spectroeye and Eyeone pro both On C1 / C7000Vp and Q1/A2000. We made our customize profile using ISO papers.
    You're right about consistency, print 1 should look like print 100 or 1000 but does it? No. it is not.

    Uniformity, I have used the TC 3.5 and laid out in SRA3 in two outs. Try to measure both test charts and you get a Delta E of more or less 2. Thought it is acceptable to some client, I am still not happy with the result.

    Last week, We finally figured out why consistency is an issue. The humidity is a big factor on Color differences. try to minimize the humid in your work area.

    My humble thoughts!
     

  6. ibler

    ibler Member

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    Billy, I figured humidity would play a factor. I remembered that when we got our docucolor, the prints were just not consistent. Then the engineers told us to control the environment where the machine was set up and to use the recommended media type.