Canon 7D + Sandisk Extreme 16GB UDMA (+ Mac?) = Unreadable .MMV Files

ian lucero

Well-known member
Ok here's a new one for me and what seems like dvxuser.com, as I haven't been able to find any info about it.

First off specs of what I was shooting on and the conditions under which I was shooting....

Location and What: Black box theater, temperature around 70°F to maybe 75°F, very slow moving movement on stage, dim (stage) lighting.

Tools: Canon 7D (all recent firmware etc.), 16GB Sandisk Extreme 60MB/s, Canon EF-S 17-55 f/2.8, MacBook Pro 13" OS 10.6.7

Settings: 1920x1080 24p, Neutral, 3200k, IS turned off, manual focus, tripod mounted with VERY little panning, for the most part locked-down.

Ok the problem:
error_message.png


I've been using Kingston 16gb cards for a while with no problems whatsoever. Yes I know, cheap. But it works and still works great. Finally decided to upgrade and get something with reputation before something bad really happens. Plop down some dough and got a Sandisk card. (note: i've had to return a previous sandisk due to it making .mov that were corrupted and unable to be saved) So I have this new card and used it for the first time on a trip to New York. The first couple shoots were fine with the new card.

It wasn't until the second shoot where these .MMV files showed up.

It is very random as I've never ever seen .mmv files before nor have them created by the camera. Very odd. I did not notice anything weird during the shoot except for the occasional "buffer" bar popping up. I figured this happened due to the temperature in the room, but shrugged it off as I've used the Canon in 80°+ weather in Hawaii with the lesser Kingstons with no problems.

As you can see in the screen grab that the first half or so of the performance is made up of unreadable(to the mac) .MMV files that don't even play on the camera. A) I'm trying to move them from the card to my external and internal drive (not at the same time mind you) with no success. You see the error message. B) I've also tried dragging from the card, a file straight into MPEGStreamClip and get:

mpegstream_filetooshort.png


C) Also tried VLC and D) also tried importing them via FCP's Log & Transfer where only the .mov show up (of course).

…….

So have any of you run into this file format on the mac and how have you been able to open them? This footage is somewhat important, but wasn't the only camera shooting. I had an HPX170 covering the tighter shot. The 7D was doing a wide, which is actually more important of the 2 as far as grant proposals and straight-up seeing the overall lighting design, etc.

Please any help to this debacle would greatly be appreciated. If this is an ongoing thing with this particular brand of card I would like to figure out and make people aware of it. Maybe this was a bad batch of Sandisk cards that I happened to run into. Completely possible. If it is an issue with the card i will most-likely return it but I would like to give the store a more detailed reason why other than, "It creates corrupted files." Maybe they can inform their supplier, etc.

Thank you for your time.
 
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I have had this problem in the past. Try using the free recovery software that is included with the card. RescuePro I believe. A serial number is on an insert in the package.
If you tried this already, then I suggest doing what I did two days again, that is calling Sandisk, or rather chatting on live help on their site, until they fill a replacement order. Mine was filled in minutes, with a UPS pre-paid label sent to my email hours later.
They have lifetime warranties on their products, so make sure Sandisk knows what is up with this card. I have the exact same card/Camera, thus same problem!
Hope this helps.
 
The problem isn't with being able to return the product. Because I bought the disk from a local reputable camera store, I can return it if I have the receipt. Rescue Pro didn't do anything to solve my problems. In fact it told me, after scanning it for over an hour, that it found Zero files. This makes no sense considering there are multiple files on the card that work fine and it didn't see even those files? At least I was able to make a backup copy using rescue pro which I think I would have been able to do with MacOS Disk Utilities.

Now that it is backed up I'm gonna try to use this copy to try other methods.

edit: the backup that Rescue Pro made actually isn't complete. The unreadable files that it copied over into the disk images are no longer the same file size as what is on the actual cf card. This tells me it didn't actually copy the (corrupted) data.

What I really need to know is: What is a .MMV file? And why can't MacOS read it and why did my 7D create these files in the first place.
 
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To me it sounds like there's a problem with
the first sectors on the CompactFlash module.
Not an unusual problem as I have seen this
kind of thing in the past with completely
different applications. If you are using
a USB adapter try moving that reader to a
different, and slower, computer. Like an
older Celeron 1.xGhz box running XP. See
if that machine can read the FAT table
and the files. I would use one of my
Linux/Unix boxes. Burn and try the live
CD from:

http://www.puppylinux.com/

Puppy has a number of disk and memory tools
built into it to test things like memory,
including hard drives and USB memory.
I've used Puppy to test CompactFlash modules
and (re)format them to many different file
systems including FAT16/32, ext2/3/4 and
many more. Puppy also has gparted built in
to it. Read on.

Once you are successful getting the files
I'd reformat it all over again. I'd guess
it's FAT32. One way to tinker with these
things is to try formatting them using a
LiveCD Linux based tool like:

http://gparted.sourceforge.net/livecd.php

Burn the image to a CD and boot your computer
from that. Plug in the CompactFlash, or SD chip,
and format the module to see if that will be
successful. Sometimes you can use one of the
Harddisk testing tools from Hitachi or Seagate
to exercise these things end to end.

Ultimately I think the Canon EOS cameras format
their removable media to a slightly proprietary
version of FAT32 so after you tested the module
you'll have to reformat it in the camera.
 
Oh, one other thing. Sometimes it's best to take
these little devils ( SD and CompactFlash Chips )
all the way back to ground zero. First bit, first
"track", first block all back to zero. I use:

http://www.killdisk.com/

and/or

http://www.dban.org/

these will reset each and every bit on the memory
module to zero. Then start your format from there.
I don't think I've ever seen a tool in the MS or
Mac arena that will do that. But then again I don't
use those OS's.
 
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