Canon EOS M Instruction Manual page 315

The maximum burst during continuous shooting is lower.
With <F> (Handheld Night Scene) or <G> (HDR Backlight Control)
shooting mode, the maximum burst for continuous shooting will greatly
decrease (p.87).
With ISO 12800 or "H" (equivalent to ISO 25600), the maximum burst
for continuous shooting will greatly decrease (p.111).
With [Chromatic aberration: Enable], the maximum burst for
continuous shooting will greatly decrease (p.164).
During WB bracketing, the maximum burst for continuous shoo During WB bracketing, the maximum burst for continuous shoo During WB bracketing, the maximum burst for continuous shooting will
decrease (p.175).
Set [A4: High ISO speed NR] to [Standard], [Low] or [Disable]. If it
is set to [High] or if [Multi Shot Noise Reduction] is set, the maximum
burst during continuous shooting will greatly decrease (p.1 burst during continuous shooting will greatly decrease (p.1 burst during continuous shooting will greatly decrease (p.160).
If you shoot something that has fine detail (such as a f If you shoot something that has fine detail (such as a f If you shoot something that has fine detail (such as a field of grass),
the file size will be larger and the actual maximum burs the file size will be larger and the actual maximum burs the file size will be larger and the actual maximum burst may be lower
than the number mentioned on page 105. than the number mentioned on page 105. than the number mentioned on page 105.
ISO 100 cannot be set. ISO 100 cannot be set. ISO 100 cannot be set.
Under [54: Custom Functions (C.Fn)], if [3: Highlight tone priority] 4: Custom Functions (C.Fn) 4: Custom Functions (C.Fn)
is set to [1: Enable], ISO 100 cannot be set. If [0: Disable] is set, ISO 1: Enable 1: Enable], ISO 100 cannot be set. If [
100 can be set (p.285). This also applies to movie shootin 100 can be set (p.285). This also applies to movie shootin 100 can be set (p.285). This also applies to movie shooting (p.181).
ISO speed [H] (ISO 25600) cannot be set.
Under [54: Custom Functions (C.Fn)], if [3: Highlight tone priority]
is set to [1: Enable], the [H] ISO speed (equivalent to ISO 25600)
cannot be selected even when [2: ISO expansion] is set to [1: On]. If
[0: OFF] is set, ISO [H] can be set (p.284).
The Auto Lighting Optimizer cannot be set.
Under [54: Custom Functions (C.Fn)], if [3: Highlight tone priority]
is set to [1: Enable], the Auto Lighting Optimizer cannot be set. If [0:
Disable] is set, the Auto Lighting Optimizer can be set (p.285).
Standard], [ Standard
Multi Shot Noise Reduction Multi Shot Noise Reduction
], ISO 100 cannot be set. If [
Troubleshooting Guide
], [Low Low
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