You are here

Sony HXR-NXU5 - audio/frame loss between SDHC cards

fairwindschance's picture
Last seen: 5 months 2 weeks ago
Joined: 01/30/2013 - 9:47am

I often shoot live events where the camera is recording for up to an hour at a time using the Sony HXR-NXU5.  

 

I use 32 Gig SDHC cards (Sandisk Extreme) and often notice loss of audio/frames (mostly audio) when the cards "split" the footage up between files.

 

The camera starts a new file after 1.97G of footage has been recorded.  Is this a setting issue on my camera or a known issue that cannot be controlled?

 

This particular camera can be outfitted with a propriatary 128 Gig hard drive (at the ridiculous cost of $700).  IF I were to purchase would this drive would the clipping issue disappear?

 

Usually this is not a problem but when filming dance or performances dependent on a musical background the 12 frame loss is very noticeable.

 

Hope this is in the correct forum spot - I'm a formum newbie and this is one of my first postings. Thank you!


Woody Sanford's picture
Last seen: 4 weeks 1 day ago
Joined: 10/19/2010 - 7:33am

Are you importing with the Sony Content Management Utility or just copying from the card?

 

I've copied from the FS 100 and VG-10 and gotten dropped frames but not when using the CMU. I've imported files from a card used in a friends NX5U with the CMU and all seemed good.

 

Something in the way it splits the file doesn't let you get the whole clip unless you go through the CMU first.


Luis Maymi's picture
Last seen: 8 months 4 weeks ago
Joined: 09/26/2008 - 4:58am
Plus Member

This also happens with the Sony AX2000. Like Woody said you can use the Sony Content Management Utility to join the split files, but I also found another altermative using Premiere Pro CS5.5 (not sure if it works on lower versions). When you import the footage from the SDHC card to your computer you need to import the folder called "BDMV" located in Private > AVCHD.  After you have that file in the computer you impport the long footage to Premiere from the folder called "Stream" and it automatically joins them without lossing the 6 or so video and audio frames. With this method you will not have to convert the footage with the Sony Utlity. 

-

"The meaning of a movie are the characters, the life of the movie is the music, but the magic is in the editing" –  http://www.lomaymi.com


Daniel Bruns's picture
Last seen: 1 year 4 months ago
Joined: 12/15/2009 - 7:46pm
Plus Member

Hi fairwindschance,

 

Great question! This is a common issue with many MPEG Long-GOP: http://en.wikipedia.org/wiki/Group_of_pictures or AVCHD video files. It is not a setting that you can change on your camcorder. Basically, the geniuses who came up with the FAT-32 file system: https://en.wikipedia.org/wiki/File_Allocation_Table for hard drives and solid state media that allows media to be read or written on a variety of operating systems for computers and camcorders. As an example, if you plugged in a hard drive or solid state drive that had been formatted with the FAT-32 file system, you could write files to the drive on a computer running Windows and then take that drive and plug it into a computer running Mac's OS X operating system and copy and paste the files onto a Mac drive. It's a robust file format in this sense because it allows a drive to be recognized by every operating system on the market today. 

 

That being said, FAT-32 does have a 4 GB file size limitation due to the funky way it was created. Your Sony NX5U knows this and so it will split files when they get close to exceeding the 4 GB limitation. In fact, it seems to be splitting them even earlier at the 2 GB mark so that it doesn't run a chance of getting anywhere near the 4 GB limitation of FAT-32 file systems (which is what your media has). Unfortunately, there is no setting that will allow you to record files that are larger than 4 or even (in your case) 2 GB, nor will having a larger hard drive. That limitation is written too deep into the FAT-32 code (which your camcorder needs to use to write files) to overcome.

 

Unfortunately, that's not the end of the inconveniences for you. That's because when your camcorder splits the MPEG Long-GOP file, it will often do so smack dab in the middle of writing a 15 frame cluster called a "group of pictures", or GOP for short. This results in a loss of a few frames at the end of a file when each file is played back separately. If your playback software doesn't see a full 15 frame cluster, it will skip that cluster which results in the loss of those few frames during playback. However, the frames are actually not "lost". They are just not being read properly by your video playback software on your computer. What you need is a "smart" software that can recognize when and where a GOP was split and recombine the split frames with the frames of the start of the next file in order to make a full 15 frame cluster, or GOP.

 

Like Woody and Luis said, you can fix this issue by running your footage through Sony's Content Management Utility or keep the folder structure and import the footage straight into Adobe Premiere, which is smart enough to know when and where the file was split due to the limitations of the FAT-32 file system and will recombine your footage for you. In addition, you can use MPEG StreamClip to combine your footage since it also has the ability to know where a file has been split: http://www.squared5.com/. It's a free application.

 

Give those suggestions a shot and see which one works the best for your workflow! Welcome to the forum and happy editing!

Dan


peter@justshootme.co.za's picture
Last seen: 3 months 18 hours ago
Joined: 10/26/2012 - 9:26am

I have a Sony HDR-NX5 and have never encountered this problem other than when the camera switches from drive A to drive B. Your issues may be arising from the class of card you are using, and should not be lower than Class 10. I have heard of these problems when using a lower class card, which cannot write fast enough to the card. I am not an expert on this and perhaps you should experiment with higher class cards. Hope this helps.


fairwindschance's picture
Last seen: 5 months 2 weeks ago
Joined: 01/30/2013 - 9:47am

Thank you all for your sharing your experience, thoughts and comments (so very sorry not to have responded sooner).  

 

I also did do some further research on my own and indeed came to similar understanding regarding the FAT32 bugaboo and now understand that I should NOT just copy the card or I will be sorry...

 

Henceforth, will utilize the Sony Content Management Utility to join the files, and, or use the MPEG StreamClip (which works great!).  Luis, I haven't tried the importing file structure directly but that is an excellent suggestion as well.  I use Sandisk Extreme SDHC cards and they are Class 10 cards... haven't had opp to locate a faster card to experiment with.  Peter et al what card do you use or recommend?  I do action - equine sports specifically. 

 

Thank you! Thank you! Thank you!