Re: Visibility and wavelength

[HUNTR2@aol.com]

In a message dated 99-07-05 14:21:06 EDT, Michael Holt wrote:

<< 
 I asked about the exact frequency of lights, seeking a color that would
 permit me to illuminate "around" particulate matter.   (I wish I'd saved
 my notes.)   As I recall, the best was a blue-green light that had
 thallium
 in it. >>

Lessons from scuba diving say blue or blue green light penetrate best by 
watching which colors can be seen at a greater depth....   red disappears 
first (at shallow depth) and blue last.    Does that shed light on the 
question?

Gene Seus