Originally Posted by Dominic Chan
The grey balance may be spot on, but you had also inadvertently reduced the 100IRE from 125 (or 120?) down to 113. You should reset the controls and redo them, only aiming for grey balance this time; i.e., adjust only 2 of the 3 colours to get the correct grey balance, do not adjust all 3 colours.
Most likely it's due the the "control displacement" that happens with some TVs. When that happens, changes to the IRE80 control may affect the IRE75 point instead (as an example), so it appears that the control has no effect (since you're monitoring IRE80 point during the adjustment.
To confirm that, reset the 20-point controls, and then make some extreme adjustments (e.g., blue set to maximum) to IRE30 and IRE80. Then run a grey scale sweep to see that effects those controls make.
You are right my friend... in our TV its starting from 10IRE with +5IRE and grows expodentially to 100IRE with +20IRE thats why my 20pt calibration doesnt touch anything above 80IRE.
BTW i want to share something that i had explained to
that was a long headache for me and this is the bug that LG Grayscale has when you have open the menu you get +30-40% up in luminance.
My main goal was when i was doing a full sweep and later i wanted to make corrections to the numbers inside the 20pt (2pt also) and that wasnt behave in edits correctly. I mean for examble i see in HCFR that at 60IRE i need a bit of red so i go normally at 20pt grayscale menu and at 60IRE i add a bit of red but i end up changing the 80IRE.
So why this is huppening? well i dont know exactly why LG did that but here is the solution to know exactly where you must edit and what is the LG Logic behind this.
Lets assume you do a full sweep grayscale measure and you see that at 100IRE you get 120Y.
Then you go to grayscale menu and you go to 100IRE and there you open in HCFR a new window and you do a free measure of the 100IRE only and that is higher. So there you will see for examble that Luminance is 195Y. Now in the Luminance setting in there in 20pt you put this exact number 195.
We close the 2nd HCFR session and we are in our old session from the 1st measure so now things are simple. We wanted to alter the 60IRE to have more RED so we see in HCFR the Measured Luminance Value at 60IRE, so this must be 72Y.
Now we open again the 20pt control in the TV and we change the IRE% Number till we see in luminance tab of the same menu in tv a number near the 72Y that will be gray. When we will see that whatever we alter in that specific ire it changes the 60IRE exactly as expected, normally from my experience to alter the real 60IRE you play with the 45-50IRE in the TV Menu
Thats it..... i hope this will help some people that brake their b...s with this LG System.. and if anyone with good english can do a helpfull how to on this i suppose many people will be thankfull.