We don't get too many comparisons like this and the Canon EOS 5D Mark III RAW video from Magic Lantern has been a very hot topic in the last few months and so is the RED Scarlet, so it is good to see some shots taken in the same environment.
Unfortunately, this sample doesn't have any direct side-by-side shots of the exact same subject, but overall, the footage looks pretty similar. So maybe you can save some cash?
Note… the video creator, Ryan Lightbourn said this in the comments:
I would take the 5D3 over a 2.5k Black Magic in a heartbeat…full frame, less moire/aliasing, better low light, fantastic stills. I'll have to wait and see how the 4K BMCC pans out before I decide on a preference there.
There are a lot more great comments in the vimeo thread
Red Scarlet vs. 5D Mark III Magic Lantern
From the comments on the video on vimeo, we gathered this… not sure if it helps much since it is a bit small.
Here's a 100% crop from the raw footage (5D left, Scarlet right):
NOTES: For more accurate results, hit the Download tab and download Original .MOV file
Stuttering in the lower angle 5D3 shots was from boat vibrations. This is not from the hack and can be fixed with warp stabilizer, but I wanted to keep full resolution in those shots.
Shot back & forth between the two cameras on the same day.
Minor grading done in ACR & RCX to match contrast. No sharpness added. Scarlet footage shot in 4k, downscaled 50% to 1080p.
My thoughts browsing through the raw footage: Scarlet has slightly more of a filmic/pro look maybe due to having more dynamic range overall? and a slight edge in sharpness. 5D3 raw has less noise, and holds more detail in the shadows. Download 1080p version for a better comparison.
Song: Hans Zimmer – Time
(cover photo credit: snap from the video)