Latest digital SLR camera from Canon is EOS 6D and the popular high-end professional camera is Canon EOS 5D Mark III, both full frame digital SLR cameras, the 6D is cheaper than the 5D Mark III and obviously misses some of the features. Canon EOS 6D vs EOS 5D Mark III Comparison from ephotozine covers both cameras by speed, ISO performance and pverall specs over prices.
The Canon EOS 6D may deliver lower resolution images (20mp vs 22mp), however this gives the 6D the benefit of lower noise at higher ISOs. The Canon EOS 6D also benefits from a smaller body, as well as built in GPS and Wi-Fi, although these last two features do have a negative effect on battery life when used. The Canon EOS 6D has noticeably less focus points, just 11 compared to 61 on the 6D, which could be another concern for some.
The optical viewfinder in the Canon EOS 6D isn’t a full size (97% vs 100%) viewfinder like the 5D Mark III, however it does have the benefit of allowing it to be swapped out for an alternative viewfinder if required. The 6D also features a slightly smaller 3inch screen, instead of the 3.2inch screen on the 5D Mark III, as well as slower continuous shooting. Another potentially off-putting negative of the 6D is the lack of a headphone socket on the 6D which could be of concern for video recording (although this could be resolved by an external audio recorder).