This little review is mostly aimed at photographers as there may be some jargon in there, that probably only makes sense to another photographer. 
This guy just arrived yesterday and i already know that im going to love this camera. I get to use it this Saturday at a wedding down in Surrey and i cannot wait.
The biggest improvement with this camera from the Canon 5D Mark II was the new improved AF. Possibly the only reason why i upgraded. For me, its worth the upgrade. Now i actually get to use the outer focus points and no longer have to focus/recompose.
When i shoot i generally shoot wide open (1.4 , 1.8 etc ) and with the Mark II i sometimes had to take multiple shots of the same image to make sure it was focusing were i wanted it to focus. not with the Mark III, one shot and thats it, the way it should be, especially with cameras this expensive.
It reminds me of the 7D in terms of handling and button layout ( although there is far more customization with the Mark III, which is nice )
Below are some images i just took. Not scientific in any way but i intentionally shot wide open with my (equally amazing ) Sigma 50mm F1.4. Tried my best to shoot in difficult lighting conditions as i could around the house ( backlighting, dark areas etc ) and the thing focused first time every time. The shot below of the spray with harsh backlighting just sums up how good this camera is. Im fairly certain the Mark II wouldnt have made this shot, particularly as i was shooting at F1.4 and using the outer focus points ( yes, they are now completely usable )
IMO, for anyone wanting to upgrade from the Mark II, i feel its worth the upgrade and this is the camera the Mark II should have been. Well done Canon for actually listening to your users.
There are tons more reviews online that go into more detail with this camera. This was really to show you ( IMO ) how good this cameras AF system is over the Mark II.
Side by side you can see the Mark III is slightly larger than the Mark II, i also found it slightly heavier. Actually handling the Mark III though is so much better.
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