yes, a good site-- there's also a great java color temperature nomograph there, where you can determine what specific correction filter you need depending upon the light source. In a message dated 6/4/2008 6:06:03 P.M. Pacific Daylight Time, eroustom@xxxxxxxxxxx writes: http://www.olympusmicro.com/primer/photomicrography/ chromeprocerrors.html Maybe you all already knew about this - funny what you can Google while looking for something else. I thought it was interesting reading. Elias **************Get trade secrets for amazing burgers. Watch "Cooking with Tyler Florence" on AOL Food. (http://food.aol.com/tyler-florence?video=4?&NCID=aolfod00030000000002)