Panasonic LUMIX DC-GH5M2GN Operating Instructions Manual page 261

7. Metering/Exposure/ISO Sensitivity – Shutter-Priority AE Mode
1
Set the mode dial to [S].
2
Set the shutter speed.
≥Rotate
3
Start recording.
•
If the correct exposure is not achieved when the shutter button is pressed
halfway, the aperture value and the shutter speed blink red.
or .
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