Thread: Chromacolor II
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Old 03-06-2018, 09:44 AM
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The EFL gun spot was extremely sharp. They initially had a problem that wherever the spot was perfectly focused on a highlight, the high current density caused the green and blue phosphors to saturate a bit and turn the white slightly pink. (The rare-earth red phosphor was linear at high currents.) This was very visible on an all-white picture like the Indianhead test pattern, where it would look like a big soft-edged pinkish ring (because when overall focus was best, the absolute best was halfway between the center and edges of the screen.) They worked on reducing the saturation of the phosphors, but I don't believe it could be completely eliminated. I can't recall if they did anything to the gun design to increase spot size a smidge to reduce the problem too.
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