Magic Lantern hack pulls 24fps Raw video from Canon 5D Mark III

posted Monday, May 13, 2013 at 4:05 PM EDT

Third-party firmware hack Magic Lantern has managed to do something absolutely incredible: pull full 24fps Raw video from the Canon 5D Mark III. While the tweak isn't ready for a wide release yet, it looks like it has the potential to come to other Canon cameras, too.

Magic Lantern is a firmware tweak that can be loaded up on some Canon DSLRs to radically boost their capabilities for professional level video controls. But the Canon 5D Mark III usually outputs video as a compressed H.264 stream, rather than the pure, Raw video. A Magic Lantner forum poster with the alias laurenco was able to get around a bottleneck that caused the camera to hit a buffer limit when attempting to record uncompressed footage. Writes lourenco:

I did a quick test in Raw mode. I wanted to see how much higher I could do above 720p. I tried 1928x850 and 1928x902. I think it was 902. 902 the buffer would fill up and video stops after 700 frames or so. At 850 I am able to get continuous recordings.

The best I am able to obtain in Raw mode right now is continuous 1928x850 at 24fps. I plan to crop the video to 1920x817 to do 2.35:1 wide screen aspect ratio, which is about 1920x817. The video will have black bars on top and bottom to output at 1920x1080.

By recording at 1928x850, laurenco was able to move around this restriction to get continuous Raw recording, which was then shifted to 1920x817, with black bars at the top and bottom to create a final 1920x1080 video file. The Magic Lantern poster has even released the firmware capable of doing so, though bugs are still being ironed out en masse. In the video below, you can see comparisons between the standard output (top) and the new Raw version (bottom). Here's another preview video, from the detailed writeup at EOSHD.

Naturally, there's a lot that needs to be tested and trialed before this gets an official Magic Lantern release. It appears that the hack requires a 1000x CF card, and that similar methods might be applicable to other bodies, such as the 5D Mark II.