Pete Bronlund
August 25th, 2018, 01:23 AM
I am making an appeal here to any users of microP2 as to whether they have experienced random cases of unrecoverable, therefore lost, long-duration recordings of the .MXF video files from this media type please.
Note that the loss is purely the video file, not any of the associated 4 audio .MXF audio channels for each video file, nor is the Proxy ever lost.
What we are seeing is that should a microP2 card (formatted in the camera) be used to record at DV a long 20min plus interview as the FIRST item onto the card then there is a pattern all too often occurring where we find first & therefore main part of the recording is lost and we have only the remaining balance past the 20mins duration as usable material..
It can also occur shooting in HD but the duration of the recording need only exceed appx 5 minutes.
We are shooting on various AJ-PX5000G cameras often in DV for an SD requirement but sometimes in AVC-intra-100/50i for HD (1080-50i).
Whenever formatting P2 media using the camera or P2 Player Plus it conforms to the legacy of FAT32. This means therefore a compliance to 4GB (4096) sized 'sectors'.
It follows that when recording the video file size never exceeds 4GB however should the recording duration be long enough then the P2 standard simply 'takes' another 4GB 'space', while the new file is given a new reference identifier and an .XML statement of the files relationship to the others. This is still a single long duration recording made up of multiple files that are appx 4GB for each 20mins appx and is treated as such in the P2 system.
For AVC-intra-100 it's just on 5minutes and a new 4GB size file is created whereas when in DV it takes in excess of 20minutes. It follows that should the duration of the recording say at DV go past 20 mins to say 21mins then the appx 1min amount will be a smaller size file compared to the bulk of the recording.
The cases of lost long records did not occur as often using conventional PCMCIA style larger form P2 cards.
Every shoot in the workflow consists of always checking the recording status by viewing thumbnails of the clips on the camera LCD. On very rare occasions should a clip be marked as having a corruption the cam-op simply uses the recovery process which in almost every case has made the recording viable.
To copy the audio and video files off the microP2 media we use a package from SAT AI Direct from NLT, the microP2 is set to LOCK before being inserted into an adapter for the standard Panasonic 5-bay slot P2 PCMCIA units.
It goes without saying but each time we experience a random loss of just the video material as in a 20min plus long recording this causes much angst and we seriously need to resolve where the problem is coming from. Should you have had any similar issues we'd appreciate your input!
Note that the loss is purely the video file, not any of the associated 4 audio .MXF audio channels for each video file, nor is the Proxy ever lost.
What we are seeing is that should a microP2 card (formatted in the camera) be used to record at DV a long 20min plus interview as the FIRST item onto the card then there is a pattern all too often occurring where we find first & therefore main part of the recording is lost and we have only the remaining balance past the 20mins duration as usable material..
It can also occur shooting in HD but the duration of the recording need only exceed appx 5 minutes.
We are shooting on various AJ-PX5000G cameras often in DV for an SD requirement but sometimes in AVC-intra-100/50i for HD (1080-50i).
Whenever formatting P2 media using the camera or P2 Player Plus it conforms to the legacy of FAT32. This means therefore a compliance to 4GB (4096) sized 'sectors'.
It follows that when recording the video file size never exceeds 4GB however should the recording duration be long enough then the P2 standard simply 'takes' another 4GB 'space', while the new file is given a new reference identifier and an .XML statement of the files relationship to the others. This is still a single long duration recording made up of multiple files that are appx 4GB for each 20mins appx and is treated as such in the P2 system.
For AVC-intra-100 it's just on 5minutes and a new 4GB size file is created whereas when in DV it takes in excess of 20minutes. It follows that should the duration of the recording say at DV go past 20 mins to say 21mins then the appx 1min amount will be a smaller size file compared to the bulk of the recording.
The cases of lost long records did not occur as often using conventional PCMCIA style larger form P2 cards.
Every shoot in the workflow consists of always checking the recording status by viewing thumbnails of the clips on the camera LCD. On very rare occasions should a clip be marked as having a corruption the cam-op simply uses the recovery process which in almost every case has made the recording viable.
To copy the audio and video files off the microP2 media we use a package from SAT AI Direct from NLT, the microP2 is set to LOCK before being inserted into an adapter for the standard Panasonic 5-bay slot P2 PCMCIA units.
It goes without saying but each time we experience a random loss of just the video material as in a 20min plus long recording this causes much angst and we seriously need to resolve where the problem is coming from. Should you have had any similar issues we'd appreciate your input!