Avatar is filled with ugly visuals. Camera movement, direction, lighting and composition are all at the service of gimmick and spectacle. There is not a single, noticeably beautiful shot in the entire film. A part of this is due to the overabundance of computer generated images that are not allowed to flow organically as they do in many animated films (such as the wonderful films Pixar Studios have been making in the past few years) but are rather constantly calling attention to themselves. Peter Jackson's Lord of the Rings trilogy suffered in much the same way where
good direction was often overshadowed by over reliance on special effects and CGI.
Aside from all this, the 3D in the film makes it even uglier. The aesthetics of cinematography are largely depended upon an artists ability to frame his or her subject matter, to use form and movement to convey to us images that are beautiful and meaningful, to touch us in emotional, intellectual and spiritual ways. This is made impossible with 3D which makes the image bleed out of the frame, calling attention to ridiculous details and working against the very biological structure of the human eye. In a regular "2D" film one notices depths to the image. In 3D there is no depth, only added layers all of which are completely flat, stacked on top of each other.
That being said, I do kind of want to see Avatar again in 2D. Perhaps the 3D experience totally ruined whatever good direction Cameron may have exhibited in the film. I have semi-liked many of his films in the past (and I loved the first Terminator) but the thought of sitting through the film again hurts my brain in terrible and frightening ways.
Here are a couple of visual examples from Avatar:
Avatar's Sam Worthington
"Na'vi" in Avatar
And here are a couple of shots from two wonderful visual masterpieces, Woody Allen's Manhattan and Carol Reed's The Third Man
Woody Allen and Diane Keaton in Manhattan
Orson Welles in The Third Man