Digital BW, The Print

Interesting that the colour shift is extremely close - really only the
luminance figures have anything close to a meaningful difference.  Am I
reading your numbers correctly?  Where you have a positive change in L* is
that a fall in L* or increase?  I would also suggest that the differences in
L* are trivial.  For example, a change of 0.67 of a base of around 53.55 is
a mere 0.012 in density.  It is, however, very comforting to know that the
UT7 and Epson K3 inks are in the same league.  This should give UT7
purchases a lot of assurance with respect to the relative endurance of their
ink.


> From: Paul Roark <paul.roark@...>
> Reply-To: <DigitalBlackandWhiteThePrint@yahoogroups.com>
> Date: Tue, 16 Aug 2005 16:05:43 -0700
> To: DigitalB&WPrint <DigitalBlackandWhiteThePrint@yahoogroups.com>
> Subject: [Digital BW] Fade test -- 4800 v. UT7, MIS old v. new, & Kirkland
> 
> My latest fade test (compact fluorescent light) reached 600 hours.  So, I
> have some initial fade results.
> 
> The short version:  UT7 showed less fading than the 4800 "Advanced B&W" mode
> prints both in the highlights and at 50%; the MIS new base does not appear
> to negatively affect UT performance; and inks on Kirkland paper are very
> stable.
> 
> 
> Notes: The results are expressed in Lab and were read with the X-Rite DTP 22
> spectrophotometer.  The same paper batches were used for all comparisons.
> The results shown are the average of 3 readings.  The affects of the
> variability of the spectrophotometer were minimized by reading comparison
> test strips at the same time.  The actual starting, pre-fade densities may
> vary from the control test strips, but comparisons based on the pre-fade
> measurements resulted in similar comparisons.  The UT7 comparison test
> strips were printed with "neutral" curves that were modified to match the
> density and tone of the 4800 test strips as closely as reasonably possible.
> 
> 
> Spectrophotometer readings:
> 
> EEM 0% (paper white) Control: (96.83, 1.03, -3.49)
> 
>                      Change: (-0.04, -1.4, 4.48)
> 
>       Comment: As we know, the paper yellows.
>                This will affect mostly the highlight results.
> 
> 4800 EEM AB&W Neutral 5% Control: (92.76, 1.20, -3.79)
> 
>                          Change: (0.16, -1.49, 4.92)
> 
> 7600 UT7 Neutral 5% Control: (92.79, 0.83, -3.98)
> 
>                     Change: (-0.02, -1.59, 4.94)
> 
> 
> 
> 4800 EEM AB&W Neutral 10% Control: (88.35, 1.07, -3.11)
> 
>                           Change: (0.52, -1.39, 4.73)
> 
> 7600 UT7 Neutral 10% Control: (89.18, 0.34, -3.34)
> 
>                      Change: (-0.04, -1.41, 4.53)
> 
> 
> 4800 EEM AB&W Neutral 50% Control: (53.55, 0.72, 0.38)
> 
>                           Change: (0.67, -0.55, 2.04)
> 
> 7600 UT7 Neutral 50% Control: (54.04, 1.96, -0.27)
> 
>                      Change: (0.08, -0.68, 1.93)
> 
> 2200 UT7 New Base 50% Control: (53.53, 1.17, 0.14)
> 
>                       Change: (-0.14, -0.68, 2.04)
> 
> Kirkland UT7 50% Control: (56.54, -0.52, -4.17)
> 
>                  Change: (-0.33, -0.56, 1.24)
> 
> 
> 
> Paul
> www.PaulRoark.com