Digital BW, The Print

Carl,

In the first Y =  equation, are you using the symbol ^ to 
represent "to the power of" 3?

Thanks,
Mike

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, Carl Schofield 
<scho@m...> wrote:
> Steve,
> 
> You can calculate density from either the "L" values from the LAB 
data 
> or directly from the "Y" number in the XYZ data:
> 
> If L > 8
> Y = ((L + 16)/116)^3
> Else
> Y = (L * 27)/24389
> 
> Density = -log10(Y)
> 
> I have no problems with the eye-one rubbing on the patches when 
using 
> the strip reader.  I have attached an 8.5x11 inch sheet of 
pictorico 
> high gloss white film to the underside of the back edge of the 
strip 
> ruler so the feet on the eye-one slide more smoothly when making 
strip 
> measurements.
> 
> Carl
> On Monday, December 22, 2003, at 02:28  PM, Steve Kale wrote:
> 
> > From my other posts you can see that I am trying to improve my 
> > knowledge of QTR.
> > However, I also have a very basic question potentially applicable 
to a 
> > broader
> > audience.  How can I use an Eye-One Photospectrometer to 
calculate 
> > density values.  I
> > can see how to take a spot measurement of a patch and get an 
answer in 
> > a variety of
> > colour spaces but how are these then converted to density values?
> >
> > Thanks
> >
> > Steve
> >
> > PS:  do others have problems with the Eye-One rubbing along the 
> > surface of patch
> > strips when using the strip ruler?
> 
> 
> [Non-text portions of this message have been removed]