This is the next preset of Danne's build I wanted to give a try on the Canon EOS 5D Mark III. The UHD mode records at 3840x1536 @23.976fps. At 12bit I got a minimum of 15sec, but often way longer than that. The crop factor should be somewhere around 1.5x, so you get a bit more sensor area than APS-C and again a bit more than you get with 4K from EOS 5D Mark IV (non RAW).
The biggest disadvantage with that mode is, that you have to disable the liveview while recording. Otherwise the cam will stop after 2 or 3 seconds. This means you have to plan your shot very well before recording. I tried to do so on my Glidecam - difficult but possible.
There was no rescaling done - this is the original resolution coming from the camera! And the footage was not sharpened.
Gear used:
Canon EOS 5D Mark III
Canon EF 16-35mm f/2.8 II USM
K&F Variable ND8-ND128
Audio-Technica Pro-24 (modded)
Glidecam HD-2000
Lexar 1066x 32GB
SanDisk Extreme Pro 128GB 170MB/s
When comparing this with my last small test video in 5.7K anamorphic mode, my conclusion is:
5.7K looks more cinematic to me, while UHD is without doubt sharper (but no idea if you see it, because of youtube compression). 5.7K mode uses the full sensor width and has a nice field of depth. In UHD mode you'll have to focus very very well and it shows the smallest weekness of your lens.
https://www.magiclantern.fm/forum/index.php?topic=25180.msg229197#msg229197
