Sandisk 16gb 30mbs PROBLEMS

[Kelly Langerak]

Hi has anyone come up with this issue or know what might be the problem. I've done my google search, but no help there.

I got this message when I tried playing the files in QT: An invalid public movie atom was found in the movie.

I was shooting a wedding speech when all the sudden the screen froze, a meter icon appeared on the right hand of the screen and then the screen went black and read Error 02 "take out the card or reformat." something of that nature.

So I pulled out the card and reinserted. It worked fine. Then the screen froze again, but when I turned off the power the screen stayed on as well as the power to the camera. It wouldn't turn off.

So after looking at what I have on the card today I found this:


Clips 1-8 are corrupt.

Anyone else have this issue. Were you shooting long takes? Was the room really warm? Did you find out that the card was the problem? Did you fix your corrupt files?

I've tried opening the files in VLC with no luck.

[Bruce Foreman]

The 30Mbs cards that have UDMA "may" be OK, earlier cards without UDMA are not really recommended. In some situations they may seem to perform OK, in others where there is more scene detail the card may easily fail to keep up with the camera.

At the time I ordered my first CF cards for my 7D, SanDisk was having a rebate on their Extreme IV cards that turned out to be 45Mbps and I ordered two 8GB cards. When I went back for one more the 45Mbps cards were gone and the one I ordered was 60Mbps.

You need to seriously look at SanDisk Extreme IV all of which have UDMA.

Don't skimp on the media, you paid over a grand and a half on the body.

For video (and fast still burst) the 7D needs a fast CF card with UDMA.

[Barry Nolan]

Kelly,

The 7d writes the MP4 encoded picture to the memory card at 5.5 MB/s. Canon adds a little headroom for safety and recommends a Class 6 SDHC card. It has a min write speed of 6MB/s. That’s MegaBytes with a Capital B. At 8 bits per Byte that would be 48Mb/s. That’s Megabits with a small b. If you were using a 30Mb/s card, which is way under Canon Specs, this would explain your problem. The Cards Class number is the supposed guaranteed speed of the card, but in practice they do sometimes run faster . If they start to heat up, they start to slow down. You may have been marginally on the edge of the correct writing speed. Buy a card that meets Canons Specs.

Barry

[Joe Lawry]

Sandisks & 7Ds hate each other... there are a number of threads on other forums about issues with sandisk cards. Stay away in general.. i've yet to find a model of Sandisk CF that works consistently..

[Bill Pryor]

I'm sure he meant MB/s, not Mb/s. The Sandisk Extreme III that are 30MB/s are UDMA cards. There were some designated Extreme III that were NOT UDMA. Sounds to me like his problem is a bad card. That happens with any card, unfortunately.

I've been using the Sandisk Extreme III 30 MB/s cards since last September. No trouble at all. I know of one other person who had a bad one.

Any time I get a new card, I let the camera run and fill the card up all the way, then check to be sure the files will load. That won't help me if it goes bad later but at least I know a new one works.

Also, I format the card in camera, not in the computer, and reformat it in camera after I copy over my files.

[Jon Fairhurst]

I bought my 5D2 in December 2008 along with three 4GB SanDisc Extreme III 30 MB/s cards. More recently, we got some 16GB SanDisc Extreme IV cards. I have yet to see an error on these models.

[Randy Panado]

Originally Posted by Joe Lawry

Sandisks & 7Ds hate each other... there are a number of threads on other forums about issues with sandisk cards. Stay away in general.. i've yet to find a model of Sandisk CF that works consistently..

I'm sorry to say, but I have had the exact opposite experience. I've used Extreme IIIs, Extreme IVs, and the new Extremes and have had zero issues with sandisk. Never had the buffer come up, never had a corrupt file. That's not to say that it hasn't happened to others, but to say that the two HATE each other is a bit far fetched.

Sometimes people buy used cards on ebay or from ebay sellers that aren't genuine sandisk cards, that may attribute to some issues. But in my experience, along with many others in the wedding filmmaking industry, there's been little to no issues with the 7D and sandisk cards, or even the 5dmk2 for that matter.

Cheers

[Andy Wilkinson]

Ditto. ZERO issues with these Sandisk cards and the 7D - I totally disagree with the statement that the 7D and this make "hate each other". The best cards are made by Sandisk and ATP, in my opinion. Any manufacturer can produce the odd dud - fact of life but buy good makes from reputable suppliers (fakes do exist), always buy the fastest cards you can afford and always test them fully before use (exactly as described earlier)...those are the golden rules.

[Jon Fairhurst]

Because the Sandisk cards are so popular, it wouldn't be surprising to read about some failures. A less popular brand might have a much higher percentage of failures, but fewer problem reports.

[Kelly Langerak]

Yep, I'm def using the correct cards. they are 30MB/s* and UDMA.

I think it was that the card overheated and the buffer ran out.

So does this mean then, if I'm recording and it freezes, don't turn off the camera and let the buffer catch up?

Is that what the little meter to the right of the screen means?

[Bill Pryor]

You should never see a buffer when shooting video. It might come up if you fire off a couple of stills before stopping the video recording. I did that by accident one time and a buffer warning came up, but it said "buffer." If the camera is overheating there is a red, I think, symbol that comes up. I've never seen it on my camera. What did the symbol look like?

[Wayne Avanson]

same here. using San Disk 16's - III, IV and the new ones (two of each) never had a problem with them in either the 7D or 5D2.

[Derek Reich]

Yesterday I got two files with 'invalid public atom' errors (what the heck IS that anyway?) on my SanDisk Extreme 60MB/s UDMA 16GB card. I was too rushed to read all the way through the thread here, is this possibly a corrupt card?