QTR-Quadtone RIP

Terrence

Although the difference is small, you have raised my curiosity. 

I have gone through my notes from the creation of the User Guide and I
cannot find any details regarding the origin of the table. My recollection
is that at some point I revised the spreadsheet to correct for a
discontinuity in the formula for conversion of CIE LAB to XYZ (used as part
of the L*/density conversion) as documented by Bruce Lindbloom at this
reference:
	http://www.brucelindbloom.com/index.html?LContinuity.html

It seems that when I revised the calculation, I failed to update the User
Guide with new values. This is consistent with the observation that both the
differences you observed and the differences in the two formulas only apply
to densities above 2 (approximately). 

The spreadsheet is consistent with the above reference and I would consider
it to have the correct values.

Thanks for pointing this out - yet another reason for me to update the user
guide.

Tom Moore

 

> -----Original Message-----
> From: QuadtoneRIP@yahoogroups.com [mailto:QuadtoneRIP@yahoogroups.com] On
> Behalf Of televe47
> Sent: Wednesday, December 27, 2006 6:33 PM
> To: QuadtoneRIP@yahoogroups.com
> Subject: [QuadtoneRIP] Ideal Densities Question
> 
> Tom Moore's User Guide and the "CurveEvalV2" spreadsheet both give
> tables of ideal densities.  At densities above 2.00 and % steps above
> about 45%, the numbers start to diverge.
> 
> Which table is more correct, or are both tables close enough that it
> doesn't make much difference?
> 
> Cheers,
> 
> Terence Lowe.
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