Digital BW, The Print

In an art catalog I saw another set of "tests" that tended to show dyes were
almost as good as pigments when they were sprayed with a UV spray.  However,
when I read the fine print, the trick used became clear.  They had coated
the dye test strip with a UV blocking subtance, and the pigments were
totally un-protected.  Then they used only UV light for the fading.  Of
course, the UV blocker was essentially opaque to the UV light, whereas the
pigs got a full dose of very damaging UV.  Using UV light as the test source
terribly skewed the results.  As Wilhelm has noted, in indoor display, it is
visible light (assuming no serious airborne pollutants) that does the
fading.

Paul
www.PaulRoark.com