Hi. It seems like the only thing changed from default on your tv is the white balance, and a few minor things like the aspect ratio.
I believe that model tv has CMS (color management controls) and you have the color set to auto. I've yet to see a samsung of the at least 100 I've done that doesn't need any color work. If that model (which I've yet to do) doesn't have custom controls, I'd still be willing to bet it should be set to native rather than auto.
Also this tv "may" not clip whites at high contrast, but no need to take the risk. Drop your contrast down to somewhere between 75-88 for most samsungs and the backlight control cam take care of max light output. Last comment, did you say he "calibrated" the tv using batman? I really hope you meant he just used it as a demo for black levels. Even so it's not a great demo anyway (for that).
Color controls weren't touched, as well as many other controls that should have been. Your tv may look good but I guarantee it could look better, and if you lived near Ottawa I could prove it with a 10 minute demo.
Please watch this video if you need the best picture possible for your UN46C6900 TV. Some of the White balance settings maybe used for other 6000's models and maybe 7000's models. It all depends.
This is if you reset your TV Manufactures settings in the Service Menu. Your settings will disappear and you need to get the TV readjusted if not, it will probably not even turn on.
http://www.youtube.com/watch?v=Ytc2OIt2lJE
This is the Calibration settings.
http://www.youtube.com/watch?v=tNx14S4xuy4

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