Canon EOS R3 Advanced User's Manual page 370

View Assist.
When played on the camera, these movies may look darker and have lower contrast than
movies recorded with a Picture Style applied, due to Canon Log image characteristics,
which are intended to ensure a wide dynamic range. For clearer display that makes it easier
to check details, set [View Assist.] to [On].
Setting this feature to [On] does not affect movies recorded to the card, which are
recorded using Canon Log characteristics. Similarly, HDMI video output has Canon Log
characteristics, and View Assist is not used for it.
Note
[ ] is shown on the information display screen during movie recording with View
Assist.
When set to [On], View Assist is also used with magnified display.
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