Disappearing footage

M

matthewwest

New member
Hello all I'm new here, so thanks in advance for any help you can give.

I'm going to start off by saying that I'm not a professional camera man, or even a serious hobbyist. I am a CE veteran (used to run the testing lab at Circuit City, ran the company tech blog), so I know how most of this stuff works.

A few months ago I ordered an HMC150 to use for work purposes. Shooting event footage, CEO interviews and videos, etc. Trying to save the company some money. For the most part, the camera has worked fine, except for two occasions, both of which involved the CEO.

What happens is that I shoot footage, play it on the camera, then turn the camera off. I then remove the card from the camera, insert it into the card reader in my MacBook Pro, and open Final Cut Express. I start the log and transfer, and get a message about a non-supported file structure.

At this point, if I remove the card and put it back in the camera, I get a "no data" message. All of my footage is gone, and has to be reshot. CEO is not amused, and is suggesting we return the camera. I can't disagree.

I'm using 16GB class 6 Transcend cards. I called Panasonic today, and the tech guy told me it's likely a problem with Final Cut Express, even though it works perfectly fine 95% of the time. I'm wondering if one of my SDHC cards is bad, but it seems like if that was the case, I wouldn't be able to record at all, or there would be playback issues in camera.

At this point I've asked purchasing if we can return it to CDW and get a DV tape model instead. I know there's probably some logical explanation to this, but the whole memory card thing is starting to seem a bit too risky for me.

Any ideas on what might be causing this problem?
 
1. What "card reader" are you referring to? Is it an separate SDHC card reader that you use with the USB2 slot in the MBP?

2. Are you write protecting the SDHC card every time before you unload the footage?

3. What version of FCP, QT, and OS X?

4. What setting did you shoot with on the 150?

5. Are you formatting the SDHC card in the cam?
 
While I can't explain how the card's data got corrupted, I would recommend copying the card's contents to a hard drive before initiating the log/transfer process, as well as write-protecting the card as soon as it's ejected from camera.
 
1. I'm using an AFT 7-in-1 reader that goes in the ExpressCard slot.

2. No

3. Final Cut Express 4.0.1, OSX 10.5.6, Quicktime 7.6

4. The first time I was shooting, it was the lowest setting. Today it was the highest.

5. No. And as I read here, I think that could have something to do with it. In fact, on both occasions the card had other various files on it. I routinely edit video on the MBP, copy the final version to a SD card, and use that to transfer files to my work PC. I didn't think there was any problem popping a card into the camera and just shooting. I'm thinking that may have been a bad move.
 
Every data on the card must stay intact. So, you probably have a corrupted data somewhere.

And Transcend card are not bad, but there is some of them that can be bad. Maybe a Panasonic card would be better.
 
If the footage does play back in the camera, then obviously there isn't a problem with the card. Maybe it was FCP like the Panny guy said.
 
To the OP: Forget what FCP and the camera indicates, are you able to browse the content of the card within Finder?

Is there a disclaimer associated with whether we can eject card out of the camera anytime as long as the camera has stopped recording? In other words, is there a chance of the camera still writing to the card from the buffer after user has stopped recording?

Also, what is the point of write protecting the card? How does flipping that switch help you protect the freshly recorded data?

This is why I think the AVCHD logical structure is so stupid as an acquisition format.. one little corruption in the database and the NLE nor the camera is able to read it.. KISS! if it was simple individual files, it would be more durable..
 
It's not stupid.. it requires an understanding and following a few simple things. I find it to be quite intuative and I've not had problems in maintaining and archiving footage... except when human error comes in. It's really been quite robust all in all.
 
Justyn said:
It's not stupid.. it requires an understanding and following a few simple things. I find it to be quite intuative and I've not had problems in maintaining and archiving footage... except when human error comes in. It's really been quite robust all in all.
Click to expand...

Would you or would you not agree that with a more complex data structure and more auxiliary files involved, it lends a greater chance for any one of those files go to corrupt and thus screw up the entire database? Wouldn't you then agree that a simple structure consisting of only individual video files is more reliable in this respect?
 
D.R. Gates said:
Just maybe it's the labyrinth of complexity that leads to reliability?
Click to expand...

If every single auxiliary file on the AVC card is required and folder structure needs to be preserved, that will not result in greater media robustness. It just means more things can go wrong and get corrupted. As soon as a single non-MTS file goes, the whole logical structure is compromised.

It's a cost vs reward thing.. very little advantages are gained at the cost of greater complexity and less robustness.

For something like blu-ray dvds, such a data structure makes sense because data corruption is much less likely on an optical disc.
 
Be Careful

Be Careful

Be careful with MBP and USB readers and USB flash.
Always write protect your SD card.
I had a MBP corrupt a USB flash drive that contained XML files created on a PC. I even went back to the PC recreated the files, then opened them on the PC to check and they were fine but when I connected to the mac they were corrupt again.
Always eject devices before removing them PC and MAC (if they dont eject wait or close the programs that used the drive).
And becareful on how much power you place on the USB ports. Best I can figure is the above problems occured when I had a Microsoft Mouse and a WD320 USB powered drive connected on the MBP USB ports.
If fact the WD320 wont start sometimes when the mouse is connected even when running on mains power.
The USB flash drive is now useless. And this is about the fifth one that the MAC has destroyed.
Also use you camera as reader USB2 connected the MAC (no power issues)
 
booggerg2 said:
Also, what is the point of write protecting the card? How does flipping that switch help you protect the freshly recorded data?
Click to expand...

OS X will occasionally try to write to mounted, non write protected cards, especially when Spotlight is operating.

This is true for p2 cards as well.

Remember, we are all here to contribute and assist, and some of us have different experiences than others.
 
David S. said:
OS X will occasionally try to write to mounted, non write protected cards, especially when Spotlight is operating.

This is true for p2 cards as well.

Remember, we are all here to contribute and assist, and some of us have different experiences than others.
Click to expand...

Yikes! didn't know that... And you're right.. I've had CF cards that after being read in OSX, had all kinds of OSX related folders and hidden files in them.. but only at the root level.

Would a AVCHD device rejecft a card if the Private folder was untouched but only some additional data was written to root?
 
I don't know about the additional data, but the p2 card problem is something many of DVCProHD cam owners learned pretty quickly with the HVX200.

I've been write protecting p2 cards for three years, and recently did the same with SDHC cards as well.

This may account for many L/T issues in FCP, but I think the OP failed to format the card first in the cam.
 
Although not ideal - I was able to just copy the whole file structure, then run log/trans on the new data copied. That way you never give FC a chance to corrupt the original data.
 
MadHMC150 said:
Although not ideal - I was able to just copy the whole file structure, then run log/trans on the new data copied. That way you never give FC a chance to corrupt the original data.
Click to expand...

So you had to manually rename each private folder?

Is there an application that can dump the private folder to a destination on the HD but rename the folder if there is naming collision?
 
booggerg2 said:
Would you or would you not agree that with a more complex data structure and more auxiliary files involved, it lends a greater chance for any one of those files go to corrupt and thus screw up the entire database? Wouldn't you then agree that a simple structure consisting of only individual video files is more reliable in this respect?
Click to expand...


I wouldn't agree. I dealt with this with the HVX. I didn't touch it and left it intact and it served me super well for 3 years.. same as this is doing. I do my back-up to a harddrive so in case I need to transcode again I have the files backed up.. but I also transcode in FCP and I can rename and place the footage into whatever folders I want. Its kind of like logging in bins, as you will. It's been super good from the beginning. It requires a bit of forethought and thats it.


For also backing things up to a harddisk.. I just make sure that the private folder goes inside another folder and same with the transcoded stuff.. I've found it to do what it says and if I want more control then I can do it, if not.. then it just does it's thing...


The key to a few of these items is to format the card in the cam.. have a similar procedure for whatever it is you are doing and back up your media to a few places so if something were to get corrupted or jacked up, y ou could salvage it..



I shot something today with the 150 and the client was totally in awe over the footage. he said if he didn't know better he would have thought it came off a really big high end expensive cam. It was a backhanded compliment cause of the size of the HMC.. but it delivers and it delivers in a reliable manner... Shoot he was expecting to pay for DV tapes today too and that saved a bit of cash.. DV tapes.. thats so 1999.
 
Hey Thanks for the info on the backup strategy Justyn.. I hope the HMC will work out well for me.. Just a bit anxious working with the AVCHD structure.. I much prefer simple individual file though.
 
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