There are a lot of people who love colored GI lighting and claim it enhances the look of the playfield and that is makes the colors more vibrant. This post won't change their minds even though it will show that its not true. Many people have put a red blue color GI setup into pinbot. There are 2 pictures below that will show why his is not a good idea in terms of color rendition of the art as it was designed. One pic has PBL ablae single frosted cool white LEDs under the slingshot. The other is CT single blue frosted LEDs under the blue side slingshot. Both of these shots are not touched up or color corrected. There is a spider cube in the shots to allow for white balance and white/black level setting. These shots were taken with a Nikon D80 18-200 VRII lens set at 135mm. F/5.6, 1/5 second, ISO 800 to keep exposure times down.
The white LED's looks as expected. The white are white, blues are blue, the colors of the orbits are as they were laid down at the factory.
The blue on the other hand has drastic color shifts that dramatically change the colors that the game displays. This is just 2 single element colored LED's, the effect is more dramatic when more are added. The greys on the plastics have taken on a much darker appearance and are a purple-ish color. The flipper graphic has turned blue. The blue area are a completely different shade of blue. All of the white stars on the plastic have been blue shifted. The color of the blue orbit has changed to a different blue, the green orbit is a sick greyish. The shift in the red is noticeable when you look at the area illuminated by the blue and the area blocked by the cube. The spider cube itself is a vastly different color, both the white and grey reference. The white under the slingshots is a garish blue, except where it was blocked by the starpost and you can see the clean white sliver below it.