Canon EOS R10 User Manual page 205

2.
Set the ISO speed.
ISO speed guide
Low ISO speeds reduce image noise but may increase the risk of camera/subject shake
or reduce the area in focus (shallower depth of field), in some shooting conditions.
High ISO speeds enable low-light shooting, a larger area in focus (deeper depth of field),
and longer flash range but may increase image noise.
Note
ISO speed can also be set in the ISO speed item by pressing the <
with an image displayed on the screen.
To expand the manual ISO speed setting range to H (equivalent to ISO 51200),
adjust [ISO speed range] in [
Turn the < > dial to set it.
ISO speed can be set within ISO 100–32000 in 1/3-stop increments.
With [AUTO] selected, ISO speed is set automatically.
When [AUTO] is selected, pressing the shutter button halfway will
display the ISO speed actually set.
To specify [AUTO] when setting [ISO speed] in [
settings], press the <
:
> button.
ISO speed settings] (
205
: ISO speed
> button
).