Continuous Shooting  - Canon EOS Rebel T6 Instruction Manual

C.Fn-5
This function reduces the noise generated in the image. Although
noise reduction is applied at all ISO speeds, it is particularly effective
at high ISO speeds. At low ISO speeds, the noise in the darker parts of
the image (shadow areas) is further reduced. Change the setting to
suit the noise level.
0: Standard
1: Low
With setting 2, the maximum burst during continuous shooting will greatly

decrease. Also, the continuous shooting speed may be slower.
If you play back or directly print a 1 or 1+73 image with the

camera, the high ISO speed noise reduction effect may become smaller.
Check the noise reduction effect or print noise-reduced images with
Digital Photo Professional (EOS software, p.314).
If you send RAW images to a smartphone, the high ISO speed noise

reduction effect of saved images on the smartphone may become
smaller. Therefore, if you shoot RAW images, setting the image-
recording quality to 1+73 is recommended.
C.Fn-6
0: Disable
1: Enable
Improves the highlight detail. The dynamic range is expanded from
the standard 18% gray to bright highlights. The gradation between
the grays and highlights becomes smoother.
With setting 1, the Auto Lighting Optimizer (p.123) is automatically set to

[Disable] and the setting cannot be changed.
With setting 1, noise (grainy image, banding, etc.) may become slightly

more noticeable than with setting 0.
With setting 1, the ISO setting range will be ISO 200 - ISO 6400.
Also, the <A> icon will be displayed on the LCD monitor and in the
viewfinder to indicate that highlight tone priority is enabled.
High ISO speed noise reduction
Highlight tone priority
3 Custom Function SettingsN
2: Strong
3: Disable
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