Well guys, it is with absolute pleasure that I give to you the procedure I have used for restoring my 50S10's black level of 0.008ftL
Please note that all of this is done at your own risk and almost certainly voids your warranty. I believe there is a safety risk involved with doing this as it involves removing the rear cover, exposing high voltages and risking electrocution. Please be extemely careful and do not touch anything inside the TV, especially when it is turned on.
Remove the rear cover. There are lots of philips head screws which have soft heads that can be easily damaged, so take care with them.
Locate the VR16600(Vad) adjustment pot on the SC board:
Here is what it looks like on mine:
Note the grey pot has been marked with a blue marker so that you know where the default position of it is. If yours isn't already marked, you may want to mark it.
Turn the TV on and set it to a blank input screen (for example, HDMI1 with no signal coming into the TV).
With a philips head screwdriver turn the adjustment pot anti clockwise in very small amounts until the screen shuts off. You should hear a click of the power relay when this happens. Now turn the pot clockwise very slightly so it is just above the point where the screen shut itself off.
(Basically what I think is happening here is when the voltage becomes too low a protection circuit turns off the screen. What we want to do is set it just above this point so the voltage is as low as possible, producing the deepest blacks).
Turn the TV's power switch off and then back on again. The TV should power on with a new black level
If the TV does not turn on, you might need to increase the pot clockwise a bit more.
So far I haven't detected any picture problems with performing this adjustment. I have re-measured everything with the i1d2 and it is the same as before (except for black level of course
Now I should mention that I have no idea what the long term effects of this adjustment are going to be. It is entirely possible that over time the TV will require more voltage and may even fail to power on. After all, Panasonic has designed the TV to step up the voltage and we are counteracting this. Although, I suppose we can always increase the voltage if the TV does not power on.
Another thing to consider is that this will probably have to be done several times as there are several rises programmed into the TV. I have only had 1 rise in black level on my set so I will probably have to adjust it again after the next rise.
Well, I hope this helps some of you out