I spent some time at the website Handprint yesterday, reading Bruce McAvoy’s descriptions of various red pigments. My favorite reds, Alizarin crimson and carmine were on his list of paints to avoid because of a lack of lightfastness. (Including Daniel Smith’s alizarin crimson.) I have D.S. permanent alizarin crimson, so that may be okay to use as the D.S. catalogue rates it “Excellent” in lightfastness, but that expensive tube of Schmincke alizarin crimson I bought last month is apparently quite fugitive. (Although it’s not really an issue for me at this point because I could care less if the pigment on my current paintings all disappear in a year.)
For more accomplished and experienced painters and those who enjoy reading and studying color theory and techniques, his website is a valuable reference source. The site has authoritative information about pretty much everything related to watercolor painting.
Actually, as a beginner and hobbyist, I found it a bit intimidating.