Cross posted from another thread (rainbow crusaders) I contributed to.
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Intensity of color is mostly a perceptive conditional,and relies heavily on overall realizable contrast range in a given scene. Due to the fact the the most deficient are of output in a UHP bulb is the red spectrum, the slight loss in output in this area, results in an orangish perception of the reds..when the scene being viewed 'unloads' the contrast range a bit..and reduces the output of reds to this condition. Suddenly red becomes orange..and it is PURELY a function of the contrast range in a given scene. I have messed with this EXACT 'contrast range situation with a CRT unit. The MEC tubes in my marquee projector are accused of having the same problem,when the lenses are not color filtered. The high level of color filtering has it's problems, though. Because the PJ has a superior contrast range, I immediately noticed the loss of contrast range provided by the use of a red filter. So what, red saturation increased, but at the cost of contrast ratio..and thus, 3-d effects in a given image. NOT acceptable. So, I messed mightily with the innards of the PJ, increased the PJ's inherent contrast ratio with respects to the electronics...and gained a SLIGHT increase in the perceptive saturation of the reds.
Purely a perceptive-difference equation.
Now, back to the PJ I modified for Grant. The LT 150. The reds are NOTICEABLY more correct, and much less susceptible to washout, or weakening, due to the fact that the overall realizable contrast ratio on a give scene is HIGHER than before. The effects of this are MUCH more noticeable than that of what was noticeable with the CRT modifications.
On the LT150, the other colors, incidentally, are noticeably more correct as well. So, perceptually, the PJ's overall balance is more centered to where it theoretically should be. This, by the way, was done on a CRT 1.5 gain white screen.
So, remember, red saturation in a DLP is one part bulb spectrum, and one part inherent OVERALL correctly considered scene-to-scene specific actual contrast range. So, now, Grant's Reds are not susceptible to washout, loss or shifting. They remain saturated in ALL scenes, because the overall contrast ratio is improved.
As for wHat Grant found, that's for him to say.