The Canon EOS 5D Mark II has a maximum video recording time of 30 minutes or file size limit of 4GB (whichever occurs first) for all formats. That limit is dependent upon multiple factors like camera settings, media storage size, camera power, and internal camera temperature. See details and notes below for more information.
Maximum continuous video recording times for the Canon EOS 5D Mark II
All Formats & Frame Rates
30 minutes or 4GB
If the recording time reaches 29 minutes, 59 seconds or the file size reaches 4GB (whichever occurs first), recording will stop automatically.
An increase of the camera’s internal temperature may cause recording to stop before the maximum recording time is reached.