Originally Posted by zoyd
Can you link to these posts (sorry I'm a lazy browser). I also do not think it's the AR coating based on some measurements I've done and I can probably dream up some ways of testing various theories. One thing I have noticed is in measuring the effect is that the WP shifts visually agree with the measurements on all white screens but I have a very hard time picking them out in mixed B/W video.
Sorry for the late replies. Don't have much time for this forum during the work week.
I posted some of my ideas a few pages back in this same thread here
Originally Posted by jrref
Tinting on the other hand I believe is due to the anti-reflective filter they use on the screen. Every set I've ever looked at has this to one extent or another. The Sony's less than the LGs, I believe, although the panel is the same, they have different anti-reflective filters. (This is what was "implied" to me by a knowledgeable source, but I have not way to verify it). For most, calibration will help make it less or not visible with content while on others, it's a problem.
I hope they fix all this on next year's sets.
Can you provide a link to any TV where localized tinting was verified to be caused by an AR filter? I'm not aware of any such examples. Both on CRT and Plasma, localized color tints could be fixed or reduced by adjusting voltages or re-orienting the TV (in case of magnetic fields on CRT). AR filters played no role. Uneven application of AR filters did cause some streaking/DSE type effect in some cases but it was color neutral.
Originally Posted by Tempest261
I didn't realize that these LG panels had a color filter on them. That absolutely could be the cause, and could explain how, depending on the sample, you can see multiple colors. On both of my samples I saw a bias towards yellow, red/magenta, green, and blue/cyan- depending on what part of the screen I was looking at. A slight misalignment would block some subpixels while exposing others, but which subpixels are blocked would change as you move across the screen, resulting in the color shift.
It's what I told you weeks ago (see the link in my reply to zoyd above). Yet you kept arguing with me about AR layers on the TV.
I think the reason you're usually seeing the yellowing on the left of the 65" models and on the top of the 55" models is due to the way they are cut from the mother glass. The orientation/position of the cuts and amount of "scrap" disposed at the edges (where they can hide uniformity issues) likely plays a large role.
The color filters and emitter stack design has a lot of drawbacks when it comes to viewing angles. Any of the colors that are deeper in the stack are going to see a larger drop in intensity compared to closer colors as you move off angle. LG realized the same thing and that's why they sandwiched the other colors in between two blue emitters to reduce the effect (otherwise blue would drop out very quickly off angle from just bottom layer).
In the attached diagram, you can see the the structure of each sub-pixel. The reflective cathode would be on the top, transparent anode and color filter on the bottom.
These layers are evaporated onto the substrate so it's also possible that uneven deposition will also cause uneven color temperature across the panel surface. If the native color of these "white" stacks varies across the panel, that would also contribute to the localized tints we're seeing, even if the color filters were perfect.