Samsung UN55ES6820 grainy from closeup

Hi,

I recently purchased the Samsung 6820 and i noticed if i stand closer to the TV, (2-3 feet away) the screen looks grainy.

I previously had the Sony 46inch LED (HX750) and it did not look grainy from closeup.

Does anyone have any experience with this and how to resolve it? Is it the settings that i need to change? I read that if you turn the sharpness down from 40 to 20 it helps, but i did not notice a difference.

I am using HDMI cable from my cable box (same as i did with the sony tv)

Thank.

Sometimes I like to stand close up but not always
Does anyone have the optimal settings for a 6820? Would they be the same as the 6500?
Thanks