Digital BW, The Print

> >  I am a little confused about metameriam. Is that
> > the effect one gets when viewing a print from a
> > variety of perspectives where it appears that the tone
> > of the inks seem to change?

What you are describing is a sort of irredescense, related to, but
not true metamerism. The luster papers, when viewed head on take on a
particular look. When you change your 
viewing postion, or the position of the print, it may reflect light
other than your main viewing light. Say you are looking at the print
under a track light in a Gallery. ( Lets also 
say there is a large white ceiling in the room, way above, lit by
another type of light). You stand there looking at the print as it is
lit by the track light and your eyes adjust to it 
and it looks pleasing. You now either tilt the print or move yourself
so the print reflects part of that broadly lit ceiling. The print may
take on a sheen or irredescence of a 
different color. I've read some posts that indicate that some inks,
such as Lysons newer archival dye ink, produces a golden metallic
looking
sheen in the shadow areas (shadow areas 
being the most heavily inked areas on the print) . 

Metamerism is more of an overall change of the look in the print
under different viewing conditions due
to the irregular surface of pigment particles. The print may look
perfectly neutral under a 5K 
hood in your printmaking studio, but in a gallery with tungsten
halogens, (aside from the warmer "feel" of tungsten lighting) there
may be a magenta/green crossover from
shadows to highlights, without having to adjust yourself or the print
to reflect other light sources.