Digital BW, The Print

Today I made some visual comparisons of prints I've made over the  
past few days using Nanochrome black ink in an Epson 4000 and  
printing BO mode, mostly on Hahnemuhle Photo Rag 308 and Hahnemuhle  
Photo Rag Satin.  In daylight the prints have a cold blue/black  
appearance, slightly cooler with the satin compared to regular photo  
rag.  Under halogens or normal incandescent lighting the prints on  
both papers appear dead neutral.  So this cold blue color we have  
been discussing with regard to the Nanochrome black inks (K and LK)  
appears to be a metameric phenomenon.  This NOT the ugly metamerism  
we have seen before with other inks that changes on the magenta/green  
axis, but rather a cool/neutral shift.  Seems like the black inks may  
have been designed for neutrality under incandescent or halogen  
lighting.  Dmax is just terrific on these matte papers (1.9-2.0).