5D Mk 3 'time remaining' display error???

[Peter Forum]

Hi,
This has got me puzzled.
The 'time remaining/time elapsed' display seems to be inaccurate.
This doesn't seem to impact on the recorded material in any way but there is probably a reason for it of which I'm not aware.
Shooting 1080x1920, 24, ALL-I. CF 120 16Gb fresh format. Time remaining display reads 22.09, record for 1 min as shown on the 'time elapsed' display, 'time remaining' display now reads 21.49! Huh? My basic maths thinks it should read 21.09.
What do I not know here?
Thanks from a newby.
Peter

 

[rs]

It records in a VBR. Due to that it's impossible to accurately predict how long any amount of storage will allow you to record for until it's been recorded.

 

[Peter Forum]

Thank you, maybe it would be better not to display this number then, just use the elapsed time.