[ATM] Wavelengths of light

[Jim Burrows]

At 2007-08-03 18:33 -0400, Francis J. O'Reilly wrote:

>I notice that green, the chosen color for testing optics on this 
>list is about in the middle of the visible spectrum of light as far 
>as wavelengths go. I understand that when we refer to correctiion in 
>terms of wavelengths of light we are referring generally to 
>wavelengths of green light. Is that standard promulgated anywhere? 
>Has anyone here tried otehr colors such as purple, a much shorter 
>wavelength? Or red a much longer wavelength?

It's promulgated lotsa places, e.g., H. R. Suiter, "Star Testing 
Astronomical Telescopes", p. 9, where he says the standard wavelength 
is 550 nm.  There are some slight disagreements - Texereau sez, p. 
104, "560 millimicrons".  A third opinion that I could get out of the 
bookshelf is W. J. Smith, "Modern Optical Engineering", p. 109, 
"Under normal conditions of illumination, the eye is most sensitive 
to yellow-green light at a wavelength of 0.55 microns, and its 
sensitivity drops off on either side of this peak."

         -- Jim Burrows
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