Mirror Lockup To Reduce Camera Shake - Canon EOS Rebel T6i W Instruction Manual

Mirror Lockup to Reduce Camera ShakeK
Camera vibrations caused by the mirror's reflex action is called "mirror
shock". Mirror lockup can reduce the blur caused by camera vibrations.
This is useful especially when you are using a super telephoto lens or
shooting closeups (macro photography).
Mirror lockup is enabled by setting [9: Mirror lockup] to [1: Enable]
in [54: Custom Functions (C.Fn)] (p.342).
1
Focus on the subject, then press the shutter button
completely.

The mirror will swing up.
2
Press the shutter button completely again.

The picture is taken and the mirror goes back down.
After taking the picture, set [9: Mirror lockup] to [0: Disable].

Shooting Tips
Using the self-timer <Q>, <l> with mirror lockup

When you press the shutter button completely, the mirror locks up.
The picture will be then taken 10 sec. or 2 sec. later.
Remote control shooting

Since you do not touch the camera when the picture is taken, remote
control shooting together with mirror lockup can further reduce
camera shake (p.350). With Remote Controller RC-6 (sold
separately) set to a 2-sec. delay, press the transmit button to lock up
the mirror, and the picture will be taken 2 sec. after the mirror lockup.
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