Canon EOS 5D Instruction Manual page 132

k Shooting Movies
With manual exposure shooting, AE lock and exposure compensation
cannot be set.
Changing the aperture during movie shooting is not recommended since
changes in the exposure, due to the drive of the lens aperture, will be
recorded.
When shooting a movie of a moving subject, a shutter speed of 1/30 sec.
to 1/125 sec. is recommended. The faster the shutter speed, the less
smooth the subject's movement will look.
132
Set the shutter speed and
3
aperture.
Press the shutter button halfway and
check the exposure level indicator.
Turn the <6> dial to set the shutter
speed within 1/30 sec. to 1/4000 sec.
If you set the power switch to <J>
and turn the <5> dial, you can set
the aperture.
Pressing the <B> button displays
the histogram.
Focus and shoot the movie.
4
The procedure is the same as steps 2
and 3 for "Auto Exposure Shooting"
(p.128).