Are you certain you aren't referring to simply resetting it, meaning, where it was when you first took it home from the factory (e.g. 50% of maximum level setting)?
Virtually every "suggested setting" we've seen for getting the "best" picture with HDTV's, even from different manufacturers, indicate that the "sharpness" control should be set to Zero.
What gives here? It seems counter intuitive.
Is there some technical answer that non-specialists can understand? Are the controls of all sets designed in a way that links the sharpness control to other parameters in a way that undermines accuracy of color, contrast range, motion, or anything else?
Thanks for your time and attention.

Chowhound
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