Is the pigment called opera rose lightfast or fugitive? I had always heard it was extremely fugitive, but experts don't agree.
Opera rose is a quinacridone pigment defined as PR122. According to the authoritative website Handprint, it's very reliable. In fact Handprint rates it as a "Top 40" pigment. They say: "after 800+ hours of sunlight exposure, the samples show no fading or discoloration."
Here's how they explain it:
"Quinacridone magenta PR122 is a lightfast, semitransparent, staining, dark valued, intense violet red pigment, offered by more than 20 pigment manufacturers worldwide. The ASTM (in technical report D5067-99) rates the lightfastness of PR122 in watercolors as "fair" (III, "may be satisfactory when used full strength or with extra protection from exposure to light"), but other manufacturer and independent tests rate it higher. My 2004 lightfastness tests of the nine paint brands listed above, which show color variations that suggest several different pigment particle sizes or pigment suppliers, revealed very little or no color degradation, after 800+ hours of direct sunlight exposure, in both heavy and diluted applications. This puts the pigment solidly in the "excellent" (I) category (BWS 7+)."
"For context, compare these samples to naphthol red (PR170), a pigment with a well established "very good (II)" rating, or with quinacridone rose (PV19), which is considered to have "excellent (I)" lightfastness. This is such a glaring discrepancy that the ASTM test must be flawed or unrepresentative in some way. Because Michael Wilcox relies on the ASTM documents for his pigment ratings, he has been critical of this pigment without any corroborating evidence of its fallability. I suggest you do your own lightfastness test on PR122 paints until a consensus emerges, but at present I see absolutely no reason to avoid this splendid pigment."
I haven't tried it yet in a controlled fade test, but I've used the color in a painting. You can watch the whole 12 minute YouTube video here.
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