Would you like to come up and see my etchings?

[Jaik]

Great stuff! Yeah, light from an actual light source (candle, fire, anything that isnt the sun or moon) diminishes with the inverse square law. I think you should be able to find it in gurneys book.

Heres a good site which has a lot on colour (I took a class from him once and gurney mentions the site in his book) http://www.huevaluechroma.com/106.php

Hope this helps :) Keep up the good work!