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Is the 4th Yellow Pixel of Sharp Quattron Hype?
Nom du Keyboard writes "Sharp Aquos brand televisions are making a big deal about their Quattron technology of adding a 4th yellow pixel to their RGB sets. While you can read a glowing review of it here, the engineer in me is skeptical because of how all the source material for this set is produced in 3-color RGB. I also know how just making a picture brighter and saturating the colors a bit can make it more appealing to many viewers over a more accurate rendition – so much for side-by-side comparisons. And I laugh at how you are supposed to see the advantages of 4-color technology in ads on your 3-color sets at home as you watch their commercials. It sounds more like hype to extract a higher profit margin than the next great advance in home television. So is it real?"
http://en.wikipedia.org/wiki/Opponent_process
"Kill 'em all and let Root sort 'em out"
Representing yellow with a mix of green and red is already a hack. What's wrong with software determining that the color of a pixel is yellow and actually lighting up a yellow light?
Maybe a yellow light looks more convincing than a red and green light right next to each other. I'd want to see for myself before making blanket judgments.
joking aside... some of the newer TVs with LED backlighting actually do something like this... Lighting up the picture with thousands(ish?) of independent LEDs (as opposed to a couple of souped up flourescent tubes) means they can selectively dim or turn off entirely sections of the backlighting. So when large parts of the scene are dirk, large parts of the backlighting is dimmed as well, thus increasing the contrast. It also saves a bit of power, making it easier for them to meet energy star standards, etc...
Parent is correct. Any colours around green and cyan are usually terribly unsaturated on most monitors. In fact, even in 'real life', it isn't theoretically possible to experience true cyan/aqua because the nearest direct wavelength will stimulate the red eye cone to some extent creating colour pollution.
There is a trick around this, which can be found by over-saturating the red cone. This weakens it temporarily, and then when shortly afterwards you see anything resembling cyan, it will appear as close to the true qualia as you could ever expect. The "Eclipse of Mars" illusion that follows in the below link demonstrates this for those who are curious:
http://www.skytopia.com/project/illusion/2illusion.html
Why OpalCalc is the best Windows calc
A lot of TV sets that use local dimming have a big problem showing starfields. The average color in a starfield is pretty dark, so the LED goes dim and not bright enough to show the stars. It really takes the punch out of Star Wars Special^n Edition if you can't see the stars.
That's my point though. How can a apx 515nm wavelength be a fully saturated green if the L cone is also being activated to some degree? That would be the extra pollution I'm talking about. I believe a much purer green would result if you somehow disabled the L cone. Unless you think we might see a more cyan/blue-like hue here?
To get a definitive answer, I would be interested to see what one would experience if you disabled two of the three S/M/L cones. I'm suspecting you would see pure red (disable S+M), green (disable S+L) and blue (M+L). Any research into that?
That's interesting, but it isn't "green"
What is it then?
Why OpalCalc is the best Windows calc
and so it does.
http://en.wikipedia.org/wiki/Imaginary_color
Neat snippet from the article:
"At Walt Disney World, Kodak engineered Epcot's pavement to be a certain hue of pink so that the grass would look greener through the reverse of this effect."
Sneaky!
True, but the regular LCD color gamut is smaller than the sRGB/Rec 709 gamut that is encoded in the HDTV video standard.
Basically, LCD panels use relatively wide spectrum color filters, so that they don't loos too much light in absorption. The result is a relatively small gamut - smaller than plasma or CRT.
That's my point though. How can a apx 515nm wavelength be a fully saturated green if the L cone is also being activated to some degree?
Because all light of a single wavelength is automatically "pure"; it doesn't matter what your cone responses are. The cone responses are just a code to transmit that information to your brain. Your cone responses are such that they overlap (for good reason), but that doesn't keep you from seeing pure colors.
And actually, you perceive color contrast anyway, not absolute RGB values or wavelengths. So, even if you get a group of cones to produce a pure "green" response somehow, that will simply be processed as being part of a strong red/green contrast and result just in a vivid green percept.