Is there something wrong with my 5D Mark III?

[zlatko]

Granted the white balance is off, but otherwise you are stupefied that a camera with 50% more pixels on the same sensor size and mounted to a lens that frame the subject 50% tighter gives you more details? Now I'm stupefied...

I agree. Apart from the white balance, the problems are multiple:
[list type=decimal]
[*]The D810 resolves more to begin with.
[*]The 85/1.4 is a better, costlier lens ... sharper wide open ... as most 85's are sharper than most 50's.
[*]The 85 frames the subject tighter, resolving more detail.
[*]Reducing the 85mm image to match the 50mm increases the apparent resolution of the 85 image.
[/list]

Yes, these results are typical when you stack the deck in this way. Considering the four points against it, the 50/1.4 did rather well!

One can see the same comparison on The Digital Picture (mouse over the image for the 50/1.4):
http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=732&Camera=614&Sample=0&FLI=0&API=0&LensComp=115&CameraComp=0&FLIComp=0&APIComp=0

Also, not sure which 85 that is. If it is the 85 G from 2010, then it is a much newer design than the 50/1.4 which came out in 1993, early in the EOS era and before the DSLR revolution.

 

[kram7211]

Does the AWB value change based on whether you use liveview or OVF? My camera is consistently warmer when using the viewfinder. Is this true of all Canon bodies? The only difference in the first two images is one was taken with live view and the other thru the OVF. The first image was 3800k with tint +4, the second was 4300k with tint +6, using the WB dropper in lightroom gave 2900k with tint +6 which is what I usually keep the camera on when shooting in the house.

 

[ewg963]

You've demonstrated that Nikon's 85/1.4, which is among Nikon's very best performing lenses even wide open, is sharper than Canon's 50/1.4, which is not a particularly sharp lens, particularly wide open. You make no mention of performing an AF microadjustment/fine tune, which can be critical for sharpness with fast primes shot wide open.

You've demonstrated that Canon's AWB is poor...something most of us know already (although it's better on the 1D X than any other Canon camera I've used).

I'm not convinced you've learned anything beyond the obvious...

+1