Panasonic LUMIX DC-G9M2 Operating Instructions Manual page 414

Video Settings – Main Assist Functions

Measurement Range
Measuring is possible in the range −7 % to 109 % (IRE).
•
When [Photo Style] is set to [V-Log] or when a LUT file has not been applied in
[REAL TIME LUT], this is measured with "Stop" units.
(Calculated as "0 Stop"=42 % (IRE))
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