Canon EOS 5D Mark III Instruction Manual page 232

3 Setting the Movie-Recording Size
Total Movie Recording Time and File Size Per Minute
Movie-Recording
Size
654 X
A
654 W
87 X
B
87 W
C 65 X
About Movies Exceeding 4 GB

Even if you shoot a movie exceeding 4 GB, you can keep shooting
without interruption.
Approx. 30 sec. before the movie reaches the 4 GB file size, the
elapsed shooting time or time code displayed in the movie-shooting
image will start blinking. If you keep shooting the movie and the file
size exceeds 4 GB, a new movie file will be created automatically
and the elapsed shooting time or time code will stop blinking.
When you play back the movie, you will have to play the individual
movie files. Movie files cannot play back consecutively
automatically. After the movie playback ends, select the next movie
to play.
Movie Shooting Time Limit

The maximum recording time of one movie clip is 29 min. 59 sec. If
the movie shooting time reaches 29 min. 59 sec., the movie shooting
will stop automatically. You can start shooting a movie again by
pressing the <0> button. (A new movie file starts being recorded.)
232
Total Recording Time (approx.)
4 GB Card 8 GB Card
16 min. 32 min.
5 min. 11 min.
18 min. 37 min.
6 min. 12 min.
48 min. 1 hr. 37 min.
16 GB Card
1 hr. 4 min. 235 MB/min.
22 min. 685 MB/min.
1 hr. 14 min. 205 MB/min.
25 min. 610 MB/min.
3 hr. 14 min. 78 MB/min.
File Size
(approx.)