Actually Neuro, that last image that shows the autofocus spread that looks so small and narrow, is the one I was referring to as being incorrect. Frankly both of those are incorrect. Just pick up a 6D and do a side by side comparison. True the viewfinder is not 100%, but in reality it is very close to 100%. The spread of the AF array is nowhere near as small as that second image.
The one thing I've learnt with photography is that close is never close enough. The spread of the array is not that small but not particularly larger either.
Carl ... how are you getting on with the outer focus points in low light. Mine just seem to go bonkers so I'm left to focus recompose using the center focus point.
I never use the outer points in low light. I thought according to Canon, it was the center point that was meant for low light. So that's what I use. It seems to do at least as well as my cousin's 1DX, in low dusk light outdoors on relatively still subjects...center point only selected.
The only problem I have with the 6D's autofocus, is that it will choose the brighter, more contrasty subject matter (usually behind a bird on a limb or something)...rather than the darker less contrasty subject. I am of course using only center point in this situation too...because I want the bird's eye to be in sharpest focus, etc. It's possible the 5D3 and 1DX would have a slight issue in such a situation also, but no doubt they would be better.
J.R., I'm not sure what lens and what shooting situation you would be in, where you would need to use the outer focus points in low light. In any case, don't do that, because they aren't meant for low light.
Are you in shutter or aperture priority, or manual? I assume you're at some event or wedding with a wider angle lens or something?
To all those who are happy to bash the 6D, you are ignorant, that's all. To say that the D7100 "kills the 6D", that's wrong. The D7100 is killed by the 6D starting around ISO 1250. The D7100 is only a crop camera, and thus has extremely limited light falling on its sensor to begin with.
If you don't like the 6D, don't buy it. It's not meant for you. It's meant for people who know how to make use of a camera's strengths and compensate for its limitations, like me. It's not meant for people who like to pick a certain weakness and harp on it, or who expect the camera to do the thinking for them.
I will state again, the 6D has superior image quality to all other Canons and Nikons currently in production...within a narrow ISO range from the mid 1000's up to 8 to 10,000
...which is where I often like to use it. This range is where all low light, sports and wildlife "available light" photography lives. Above that, the D4 and 1DX are superior, but not the 5D3...it's still inferior. The only thing better about the 5D3 is the autofocus and the fps. Both the D800 and D600 have worse noise above ISO 2000 than even the 5D3, let alone the 6D. They still deliver more resolution up to a point, of course.
As for landscape-only (low ISO, under 1000) photography (perhaps on a tripod...or else studio photography with flashgun or strobes)...yes the D800E is your best choice for a few more months or so, and certainly the best choice under $4000. I suspect Canon's big MP body will be priced well above $4000.
For available light photography between ISO 1600 and 8000, the 6D produces the best image with the most detail, the least noise, and similar if not superior dynamic range (in RAW anyway, but the jpegs are decent too). Perhaps it's not pulling ahead in resolution of the D800 series until ISO 6400 or so, and the D600 at ISO 4000 or so....but the 6D is way ahead regarding both luminance and chrominance noise at the native pixel level
, as in viewed at 100%...and not tipping the scales by downsampling all comparisons to 8MP, or whatever bullcrap DXOmark does. I could downsample smartphone pictures by that much of a percentage from their native, and get decent noise performance too, but so what?
I am astonished that my shots done from ISO 1000 to 1600, need no noise reduction in post of any kind. I'm also astonished that the 1DX's files have a similar large grain luminance noise structure like the 5D3's. I can understand why some I have read on here, don't want to shoot the 5D3 above ISO 1000.
The 6D has autofocus that is plenty responsive, depending on just how good and fast the lens's autofocus system and motors are. Most of the reviews I've read of the D600 say it's autofocus is not noticeably superior to the 6D's. So I don't see it as "the better camera" at all. But if you have a lot of Nikon glass, then by all means, buy a Nikon. You'll help them stay independent a while longer...delaying the inevitable.