Digital BW, The Print

The first column is Lab's L* a measure of luminosity (scale 0-100) - lower
equals darker.  The last column translates this into a density.  The two
middle columns are Lab's a* and b* which tell you you how red or green and
how blue or yellow a colour is.  (Red and green, and blue and yellow, are
opponent colours - they are mutually exclusive.  Something can't be red and
green at the same time.)  So these tell you the hue shift - ie how neutral
the patches are.  Ideally, a*=b*=0 for perfect neutrality.  What this
basically says then is that the Advanced B&W mode is very very neutral -
although as we head towards paper white we pick up some of the blue which is
in the underlying paper (remember it was printed on ISP).


> From: chipcarterdc <chipcarterdc@...>
> Reply-To: <DigitalBlackandWhiteThePrint@yahoogroups.com>
> Date: Fri, 03 Jun 2005 18:06:15 -0000
> To: <DigitalBlackandWhiteThePrint@yahoogroups.com>
> Subject: [Digital BW] Re: Holy Moly 4800!
> 
> No offense, but is there a way to summarize this in words for those of us who
> don't do step wedges and measurements?  I have no idea what tehse
> numbers mean.