Canon EOS 6D Mark II Manual De Instrucciones página 97

Set the level of background motion blur.
With [Effect], you can set the level of background motion blur. The
[Max] setting will set a slower shutter speed to increase the
background motion blur around the subject. If the subject blur is
noticeable, set [Effect] to [Med] or [Min] to reduce the blur.
To see which lenses support the <r> mode, refer to the Canon Web
site.
When using a lens supporting the <r> mode during Live View
shooting, subject blur can be corrected and the shutter speed will be set
automatically according to the setting of [Effect], regardless of the lens's
Image Stabilizer setting.
To prevent camera shake, it is recommended that you hold the camera
with both hands, tighten your arms close to your body, and track the
subject's movement smoothly to take pictures.
This effect is most effective with trains, cars, etc. that move at a constant
speed in one direction.
Taking test shots or checking the image by playing it back immediately
after shooting is recommended.
8: r Panning
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