tishk
Apr7-08, 01:55 PM
Hi guys. I'm an anthropologist really, and won't pretend I know the finer points of physics. still, this thing bothers me, and hopefully someone on this forum thinks it's an easy question.
I noticed a while back that local crafts in highland cultures - Himalayan and Andean alike! - made use of Day/Glo, neon, fluorescent colours. I think I have figured out that there is more UV light in high altitudes due to thinner atmosphere, although I don't seem to have very good sources for it. If anyone has read anything that could be used as a respectable reference, make my day.
The question that perplexes me, tho, has to do with how, while the general idea for observing fluorescence without a blacklight seems to be to conduct the experiment at noon and in direct sunlight (e.g. http://www.ucar.edu/learn/1_5_2_23t.htm), the recommended use of high-visibility materials in poorly lit situations (e.g. http://www.ipmba.org/reviews/The_Nee...ty_Apparel.pdf) indicate that there is enough uv/light to bring about an "almost magical" fluorescence also at dusk and dawn.
Could you point me to an article or two that helps explain away this apparent paradox? or a thread in the forum, at that. This one, e.g., was close to answering my question... http://www.physicsforums.com/archive/index.php/t-123480.html
I noticed a while back that local crafts in highland cultures - Himalayan and Andean alike! - made use of Day/Glo, neon, fluorescent colours. I think I have figured out that there is more UV light in high altitudes due to thinner atmosphere, although I don't seem to have very good sources for it. If anyone has read anything that could be used as a respectable reference, make my day.
The question that perplexes me, tho, has to do with how, while the general idea for observing fluorescence without a blacklight seems to be to conduct the experiment at noon and in direct sunlight (e.g. http://www.ucar.edu/learn/1_5_2_23t.htm), the recommended use of high-visibility materials in poorly lit situations (e.g. http://www.ipmba.org/reviews/The_Nee...ty_Apparel.pdf) indicate that there is enough uv/light to bring about an "almost magical" fluorescence also at dusk and dawn.
Could you point me to an article or two that helps explain away this apparent paradox? or a thread in the forum, at that. This one, e.g., was close to answering my question... http://www.physicsforums.com/archive/index.php/t-123480.html