Magic Lantern has released a continuous raw recording mode for its hack to the Canon 5D Mark III’s firmware. In testing, the camera has been outputting a 1928x850 recording at 24fps. This gives a continuous recording at a data rate to the card of 90MB/s. Imaging resource reports:
“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.”
The hack has been released in a beta format, and there are still a lot of bugs to be sorted out. The raw video coming from ML’s firmware is a 3MB per frame river of data. This requires a card that is both fast enough and big enough (24 FPS @ 3MB/frame is 72MB/second burst) to record at this speed.