Digital BW, The Print

On Jan 10, 2011, at 10:26 AM, Roger Barrett wrote:

> I've come back to this because I just had a query from a customer of mine about magenta shadows in B&W prints from his R1400. I got him to print a 51-step (QTR) target which I then measured with my i1. It looks reasonably neutral, if anything slightly green, and pretty linear too so the profile is doing a reasonable job. Under my 4700K Solux lamps it looks really nice; however, in normal T-H lighting the whole thing is unacceptably red - much worse than my old Lyson QuadBlack prints.
> 
> When I measured the 0,0,0 patch I found an L* of 4,2 but a reflectance rising fairly linearly from 0,0033 at 630nm to 0,317 at 730nm  And yes - he assures me that it is genuine Epson ink.
> 
> Am I mis-interpreting something here or does the Epson ink suffer from (severe) metamerism?

The key here is which Epson printer is involved. The 1400 does not offer light gray inks, thus is building grays from colors. So yes, this will not be as stable under differing light sources as quad black, or even as an Epson printer which utilizes grays.

C. David Tobie
Global Product Technology Manager
Imaging Color Solutions
CDTobie@...


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