Black crush issue solved
I did more tests last night for the black crush issue. This time I got a DVE calibration disc. When I displayed the DVE pattern for brightness adjust (which has three strips representing 4% above black, 2% above black, and below black, respectively), I found the TV only showed the strip for 4% above black, the other two strips did not showed up no matter how I adjust the brightness. No wonder I got the black crush problem!!! This is definitely not right! Next, I flipped around the TV settings trying to find the root cause. Finally I discovered this was caused by the "black level" setting in expert menu. my black level was set to "low" (according to most of the settings posted in this thread), when I switched it to "high", those two missing strips showed up!! Wow, this setting has a lot effects on the picture, and of cause now I need to redo all the calibration. After everything was readjusted, I put in a bluray (Transformer), now I can see much more details in the black shadow, it definitely improved the black crush issue. ON the other hand, setting the black level to "high" also make the black a bit brighter, I dialed down the brightness and raised the contrast to compensate for this. The overall picture is better than before, especially the shadow details which I could not see before no matter how I adjusted. I also want to pointed out that this setting (black level) is only adjustable when the input is set to HDMI (or maybe component, or PC RGB D-SUB, I didn't try), When the input is TV for regular HDTV watch, this setting is grayed out (set to auto).
Below are the new settings:
backlight: adjust to what you like
brightness: 35 for video input source, 51 for RGB input source
dynamic contrast: low (to compensate the black, if you don't like, set it to "off")
black level: high ---- important!!!!!!
gamma: medium (or "high" to see which one you like)
color gumlt: wide
color temperature: medium,
All white balance and color settings are defaults.
Have fun trying them out and report back what's your impression.