FYI, the shot of the Trane A/C compressor, above, shows imperfections in the vertical vanes of the plastic fan guard that may look like a jpeg error but are actually caused by the molding process. The spots on the Trane model number plate is overspray from deck paint, not camera noise. This was a really low light shot by the way.
I gave the D800 a really good chance, having owned if for nearly a year. But the focus accuracy and motion blur was something I could not master. The Sony snaps to focus on the spot nearly all the time using AFD (109 on-sensor focus points).