There's some small print. SMPTE timecode - which Panasonic uses - is weird and a bit stupid (not Panasonic's fault).
For best results:
- Set the camera to a 30P or 60P "MOV" video mode.
- Set "Time Code Display" -> "ON"
- Set "Count Up" -> "Free Run".
- Set "Time Code Mode" -> "DF" (Drop Frame).
- Set "Time Code Value" -> "Reset"
- Set "Time Code Value" -> "Current Time"
- Set the camera to a 24.000P, 25P, 29.976P, 48.000P, 50P, or 59.940P "MOV" video mode of your choice. (NOT 23.976P or 47.952P).
The displayed timecode will now run fairly accurately.
As accurately as the camera's clock at selected video frame rates of 24.000P, 25P, 48.000P, 50P, and 1 part-per-million fast at 29.976P and 59.940P.
At selected video frame rates of 23.976P and 47.952P, the displayed timecode will run 1 part-per-thousand (3.6 seconds per hour) slow.
This weirdness is because the SMPTE never defined proper timecodes for non-integer frame rates, except for 29.976P and 59.940P, which were needed for US TV.
For other frame rates, "Non Drop Frame" timecode is used, which pretends that the frame rate is the next higher integer frame rate.
So, for example if you start recording 23.976P at TC=0, the timecode will reach 1 hour after exactly 1 real hour and 3.6 seconds.
The 1ppm error for 29.976P and 59.940P is likely to be a few times less than the frequency error in the camera's high-frequency oscillator.