Canon didn’t bring 4K recording to the 5D line until the Mark IV, but the enterprising folks at Magic Lantern have engineered a workaround that enables 4K recording on the 5D Mark III.
This experimental build, available here, enables a number of different recording resolutions and frame rates, including:
- 1920×960 @ 50p (both 1:1 crop and full-frame – 3×3 pixel binning)
- 1920×800 @ 60p (same as above)
- 1920×1080 @ 45p and 48p (3×3 binning)
- 1920×1920 @ 24p (1:1 square crop)
- 3072×1920 @ 24p (1:1 crop)
- 3840×1600 @ 24p (1:1 crop)
- 4096×2560 @ 12.5p (1:1 crop)
- 4096×1440 @ 25p (1:1 crop)
- Full-resolution LiveView: 5796×3870 at 7.4 fps (128ms rolling shutter)
Magic Lantern says you can expect bugs with this build as it’s still “bleeding edge.” Also, modes with higher vertical resolution will only preview the top frame while modes with higher horizontal resolution will have the preview “completely broken.”
There’s also a 14-bit lossless raw recording mode.
Luigi Baccino put the early build to the test. Here’s some sample footage.
As a reminder, if you load Magic Lantern onto your Canon 5D Mark III you’ll be voiding your warranty. Caveat emptor.