Canon EOS 100D Basic Instruction Manual page 85

Even if you set Drive/self-timer to <i>, the camera will still shoot in
single shooting mode.
The touch shutter does not work with the magnified view.
When [6: Shutter/AE lock button] is set to [1: AE lock/AF] or [3: AE/
AF, no AE lock] under [54: Custom Functions (C.Fn)], autofocusing
does not take effect.
You can also set the touch shutter with [A: Touch shutter].
To take a bulb exposure, tap the screen twice. The first tap on the screen
will start the bulb exposure. Tapping it again will stop the exposure. Be
careful not to shake the camera when tapping the screen.
Do not hold the camera in the same posture for long periods of times
as this may cause low-temperature contact burns. Even if the camera
does not feel too hot, prolonged contact with the same body part may cause
skin redness or blistering. The use of a tripod is recommended for people
with circulation problems or very sensitive skin, or when using the camera in
very hot places.
x Shooting with the Touch Shutter
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