Physics Help Forum RGB Tristimulus Graph

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 Jul 26th 2010, 08:08 AM #1 Junior Member   Join Date: Apr 2010 Posts: 12 RGB Tristimulus Graph Hey guys, I'm just trying to get my head around the RGB tristimulus graph, as follows: Why are there negative values for red? What does it mean? I'd appreciate it if someone could help. And no, this isn't a homework question, it's part of my Computer Graphics course notes, and I'm having trouble understanding this particular concept. Thank you!
Aug 1st 2010, 06:46 AM   #2
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Join Date: Aug 2010
Posts: 434
 Originally Posted by Glitch Hey guys, I'm just trying to get my head around the RGB tristimulus graph, as follows: Why are there negative values for red? What does it mean? I'd appreciate it if someone could help. And no, this isn't a homework question, it's part of my Computer Graphics course notes, and I'm having trouble understanding this particular concept. Thank you!
Do you mean negative values for blue light? I see no negative values for red light. It looks to me like it is saying that for some wavelengths, the eye actually gets "overwhelmed" and even other colors are "blocked".

 Aug 1st 2010, 06:52 AM #3 Junior Member   Join Date: Apr 2010 Posts: 12 It's actually red light, whoever made the graph wasn't paying attention. As you can see, the red line is labelled b(x), and the blue one r(x). The labels are correct. After doing some research, I think the negative values mean that in order to replicate the colour at that wavelength, you have to add red to the colour you're trying to replicate. Yeah, it's confusing. :P

 Tags graph, rgb, tristimulus

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