P7700: Why so much grain?

Hello.  I recently purchased a P7700 and am rather happy with it......except:

I went on a hike today and set the camera to AUTO.  I found that almost all of my photos appear really really grainy.  I can't understand why.  I've got the camera set to NRW (Raw), so I excepted the photos to look rather good (like everyone else who has been posting photos.

The following photo was taken at 1/400 sec at f/ 2.0, ISO 100.  The first photo is uncropped and the second is a cropped section of the photos.

Any help / comments as to why my pictures are so grainy would be really appreciated.

THANK YOU!