--- In colorvision_group@yahoogroups.com, David Miller <dm2363@...> wrote:
>
>
> On Aug 17, 2008, at 8:22 PM, i_3d_c wrote:
>
> >
> > I've printed out the 729 patch chart from my Epson 1400 onto
> > Hahnemuhle Fine Art Pearl. For some reason, one patch consistently and
> > completely different from the printed patch. Sheet 3, row 14, column
> > A, is a pretty strong yellow yet reads as blue!
> >
> >
> >
>
> The first thing to check is this: is your calibration tile
> dirty? (What follows applies to measuring the pure yellow
> patch, as well as paper white). From David Tobie's tech note:
>
> ****
>
> Care of the Spyder3Print Calibration Tile
>
> The white tile embedded in the base of the Spyder3Print or
> PrintFIX PRO spectro needs to be clean in order to function
> properly. It can be cleaned with lens cloth or a paper towel.
> Avoid using rags or other non-lens cloth, as it may contain
> optical brighteners, which could effect white tile measurements.
> Mild cleaning solvents such as Windex or Isopropyl Alcohol can
> be used as needed.
>
> Remember your mother telling you to wipe your feet before you came
> into the house? Its the same with your spectro�s white tile: as you
> move it across printed targets, it can pick up ink and other residues.
> If you clean the tip of the spectro before calibration, that will keep
> these materials from getting on the white tile, and make keeping the
> white tile clean a much simpler process.
>
> How do you know your white tile is dirty? A visual inspection can
> tell you a lot. Another indication is if your measured values for
> paper white on optically brightened papers show as a bright Cyan,
> instead of white. If this occurs, clean both your spectro tip, and
> your white tile thoroughly, recalibrate the spectro, and reread paper
> white. If that fails to solve the issue, contact our technical support,
> for further information.
>
> ****
>
> If this doesn't solve things for you: let us know, and we'll handle
> this through a support ticket.
>
>
> David Miller
> Senior Software Developer, Digital Color Solutions
> Datacolor
>
Hi David,
I've given the tile a good cleaning first windex, then isoprolyl
alcohol. However, the results are the same -- the yellow patch is
reading L = 89.08 a = 8.35 b = -126.-6. Very cyan.
Thanks,
i.