K-amps said:
Another thing that indicates it is a 5D3, if you look at the size of the optical viewfinder opening, the 5D's is slightly larger than the 7d's ) relative to width of the Flash holder; on the mystery camera, it is more like the size of the 5D2/ FF.
In the attach pic, it's a crude approximation of the relative sizes of the view finder. & has the smallest, 5d2 is larger and mystery camera is as large as 5d2 (if not more), and visibly wider than 7d.
Thanks for the picture comparison, it made me look closer. But I cannot draw the same conclusion as you did. When brightening up the "mystery camera" picture, you see the edges of a smaller viewfinder than the 5D's inside the dark cutout - just like you see in the 7D picture you posted. On the 5D picture, there are no edges visible - only corners (inside the viewfinder). Now if you look at the mystery camera prototype and brighten it up, you do see edges - even though the camera is angled slightly to the side, you see
full side edges on
both sides. Note the blue spotted line.
To me, this still leans heavily towards the 7D.