Black and Blue >> Blacks printing with a blue caste (and how to avoid)?

Discussion in 'Color Management' started by Max Renn, Feb 13, 2013.

  1. Max Renn

    Max Renn New Member

    Feb 2013
    United Kingdom
    I hope that this is the correct forum to post on and that someone here can offer some good printing advice. I've had several cards printed using (using a HP Indigo 7500) that have had a slightly bluish colour caste in shadow areas (on both "TruCard" and 350gsm silk) >> I'm curious as to how one might avoid this in favour of a more neutral (and deeper) black. Is this related to ink levels or colour conversion, or does this particular printer have a bias? I'm using Photoshop and Indesign, and the image was Adobe RGB (1998) through the entire workflow prior to exporting to PDF from Indesign, whereby I converted to FOGRA29 (selecting Convert to destination - Preserve Numbers) as instructed. The total ink level was set at 300%.

    I'm using a recently calibrated Asus ProArt monitor (set to the AdobeRGB (1998) colourspace), and the Photoshop soft-proof shows no such colour bias, so I'm at a loss to know what steps might be taken to remedy this (and as Printed don't offer a proofing service, and have been unable to offer advice beyond converting to FOGRA29, it's difficult to experiment with alternative methods to see what might yield a better result).

    Any advise would be greatly appreciated!
  2. DanRemaley

    DanRemaley Member

    Oct 2010
    Pittsburgh, PA
    What are the values (y-m-c) in these black areas?
    1- you could convert to Medium GCR to remove or reduce y-m-c values.
    2- change y-m-c values to the same 20-30 % (makes black areas neutral).