Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 106)

Tv: Shutter-Priority AE
In this mode, you set the shutter speed and the camera automatically sets the aperture
value to obtain the standard exposure matching the brightness of the subject. A faster
shutter speed can freeze the action of a moving subject. A slower shutter speed can create
a blurred effect, giving the impression of motion.
* < > stands for Time value.
Blurred motion
(Slow speed: 1/30 sec.)
Frozen motion
(Fast speed: 1/2000 sec.)
1.
Set the shooting mode to < >.
Press the < > button and turn the < > or < > dial to
select < >.
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