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Digital Printing / Printing Issue

AngyBB Posted messages 3 Status Member -  
contrariness Posted messages 17903 Registration date   Status Member Last intervention   -
Hi,

I have recently been helping an agency specialized in digital printing as a young graphic designer.
I need some advice/information regarding the settings to use, as it seems that it doesn't work the same way I was taught until now, and searching online, the advice confuses me as it varies greatly.

- First question to make sure once and for all:
For digital printing (here on a Roland machine), when I work in Illustrator/Photoshop: do I choose CMYK or RGB? 300 or 150 dpi?

- Second question:
When I work in Illustrator, and I prepare my document, I sometimes import a cut-out image from Photoshop (I've tried importing in .psd, .eps), and when printing on the Roland, the entire cut-out/transparent area appears on a lighter-colored square, which is not aesthetically pleasing...

I make sure to use the same color profiles, and I try importing in different formats, but nothing helps, the transparency square appears...

For your information, during printing, I export the .ai to .pdf, optimal quality, Acrobat 5 compatibility (PDF 1.4). I've also tried with Adobe Distiller, but the problem doesn't seem to stem from there. I've tried both CMYK and RGB, and according to my memory, it's the same.

However, on screen, it's impossible to see that there will be a problem when printing; everything looks perfect...
Also, the software used to send the document to the Roland is called Roland VersaWorks.

Does anyone have any advice or solutions to help avoid this problem? If you need any more information, feel free to ask; I would really appreciate your feedback and advice; anything is welcome!

Thank you in advance.

5 answers

  1.
    contrariness Posted messages 17903 Registration date   Status Member Last intervention   6 243
     
    VersaWorks is a RIP.. and it doesn't like transparencies too much... (at least for the version I know, which is not the latest). So image cutouts made with transparency can cause problems..

    However, since you are creating a PDF version 1.4 it shouldn't be a problem since this version does not accept transparencies and thus creates pixelation..

    But perhaps that is where the problem comes from.. if the pixelation does not give a perfect white and that ends up in the print.

    Try adding a stroke for the cutout and using it as a mask in the image. The area defined by the mask should be neutral.
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    1. AngyBB Posted messages 3 Status Member
       
      Thank you for this answer. So instead of cutting out in Photoshop by creating a transparency area, you advise me to use a path that I will convert into a mask to import it into Illustrator, in order to maintain the transparency?

      But this white you mentioned, is there no way to see it on screen beforehand to avoid printing a bad job?

      I will check our version of Versa Works but I doubt it's the latest one.
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  2. contrariness Posted messages 17903 Registration date   Status Member Last intervention   6 243
     
    Personally, that's what I do, and I've never had any problems with old stuff (software and RIP)..

    In Photoshop, you indicate that the cropping trace is the mask to be applied.

    In Illustrator, the mask will be applied as it is saved in the image at the same time.

    To check a PDF file, you need at least Acrobat "Pro".. the "Pitstop" plugin provides more information, allows you to edit the file, etc...

    But already with Acrobat "Pro" you can know the composition (colors) of any surface of your page via the "Show separation and color warning preview" function. You provide a separation profile to avoid being in RGB and move the slider to visualize the CMYK distribution in %.
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  3. oXyde68 Posted messages 793 Status Member 352
     
    Hello,
    For digital printing (here Roland brand machine), when I work in Illustrator/Photoshop: should I choose CMYK or RGB? 300 or 150 dpi?

    CMYK, so far it has always been the same (Additive system), and 300 dpi for optimal results (Those who can do more can do less).

    Have you tried completely destroying the background pixels (destructive cropping)?
    Do you have the ability to create your layouts in InDesign?

    Before sending your file to the RIP, open it in Photoshop and flatten it (without saving it!) and check that you don’t have this problem that appears.

    --
    Best regards,
    oXyde68
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    1. contrariness Posted messages 17903 Registration date   Status Member Last intervention   6 243
       
      For composite printing, I don’t really agree with you on converting to CMYK. Printers are most often equipped with 6 or 8 colors, and when we need to reproduce a photo (which will not be printed in color separation), it's preferable to send the data to the RIP in RGB in order to have the maximum color information and allow the conversion engine to use the 6 or 8 colors of the machine.

      The conversion to CMYK will limit the color space and cause a loss of brightness in the image.

      I am printing posters on a PRO9880, and sending in RGB corresponds better to what can be seen on the screen.
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    2. oXyde68 Posted messages 793 Status Member 352
       
      Never had a problem with the current RIPs.
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  4. AngyBB Posted messages 3 Status Member
     
    So apparently the problem doesn't come from the fact that we work in CMYK or RGB. For my part, I was used to working in CMYK 300dpi, and 150 or 72 when the documents started to be very large and the file became heavy.

    Our Roland machine only has 4 color cartridges.

    The problem would therefore come from how to cut out the image and import the file. In what format do you import your cut-out images? .eps? .psd? other?

    To answer the questions, I believe I already use destructive cropping, that is to say that once cut out, I delete the unnecessary pixels (like the eraser tool).

    I also know how to use the mask tool, which allows you to hide troublesome elements of the image without totally destroying it, which allows you to make elements reappear/disappear at will.
    And I also know how to use the path that I convert into a mask to hide the area I don't want to show.

    I should try using the last two methods to see if the problem comes from there; it’s true that I usually use destructive cropping (if that’s indeed what it’s called).

    To respond to oXyde68, I use InDesign little when it comes to creating a single panel, etc. It's true that I use InDesign more often when certain elements are repeated. However, I could do a test to see if that changes something in the printout.
    And isn’t an image directly flattened when imported into Photoshop?

    Thank you for your advice, I will try these different methods on my next mock-ups, and I will keep you updated to let you know if the problem is resolved or not.

    Feel free to suggest anything else!
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  6. contrariness Posted messages 17903 Registration date   Status Member Last intervention   6 243
     
    File formats such as EPS, PSD, and even PDF retain the path of clipping included in an image.. (there are other formats as well, but these are the most common).

    Try to do one thing.... I don't know how you send your job to VersaWork, maybe via a print spool, or something else, but try this:

    Make a PDF of your document and drag-and-drop it into the VersaWork window (the job queue window). If you still see that area in the clipped part during printing, you can then analyze its content with Acrobat "Pro" and its "color separation preview" tool.. It will indicate if there is a % of residual color. If there is nothing... then you may need to look into the profiles included or not in the image.
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