Digital BW, The Print

What I have to watch with my DataColor unit is my lifting the meter too soon.  The way I know I've done this is that the color values (Lab A and B) will spike in one direction or the other -- way off the trend line.  I see this when I'm looking at the graphs in Excel.  What I do to correct the problem is simply go back and remeasure the patch correctly.  I simply write the new, correct values into the Excel boxes and save the file.

Paul
www.PaulRoark.com 

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, Terry Ritz <t.ritz@...> wrote:
>
> On 12-05-31 4:57 AM, "wolverinemsu" <bchug@...> wrote:
> 
> > Sometimes when using the Munki, a
> > patch or two are not measured "correctly" in that the "L" values don't follow
> > the rest of the curve.  This is especially noticable in the darkest patches,
> > where the values may actually reverse (darker patches give higher "L" values.
> > I export the L*a*b values from the scanned palette and import them into Excel,
> > where I can plot them ("L" vs. % black).  It becomes very apparent which
> > patches fall off the curve.  I remove (delete) the offending point(s) then use
> > a 6th order polynomial trendline to generate a smooth curve and use the
> > coefficients to generate a smooth set of points.  These are then copied into
> > the "L" values in the text file used to drop into the QTR-linearize droplet.
> > The resultant linearization values, when copied into the QTR ink descriptor,
> > give a nice smooth curve.
> 
> This looks interesting wolverinemsu.
> 
> A question. How do you know that those particular patches have been measured
> incorrectly, as opposed to being a legitimate product of QTR, your ink set
> and the paper you're using?
> 
> Terry.
>