Corrupted files due to airport security?

jhefti

Anyone ever have this problem?

I recently came back from a shoot in southern California. I was in a rush to get to the airport, so I just took my two Lexar 1000x CF cards out of my two camera bodies without downloading the files, and put them in my carry-on computer bag.

After I passed through airport security and was waiting for my flight, I downloaded them. Each and every file was corrupted, though most still had enough intact data to be recognized as a photo. I have attached a representative shot below, taken from a screenshot of the PM thumbnail. I was shooting RAW, full size.

Both cards were corrupted. Each of them came from a different Canon 1Dx bodies, and the LCD images looked fine when I was occasionally chimping throughout the shoot. I ran image restore and even went into the files to find some corrupted headers and lots of registration errors. The image restore program I ran (also from Lexar) recognised tens of thousands of images, though in reality there were about 600 RAW files.

Before re-formatting, I tried uploading and downloading some jpegs I had on my laptop (a MacBook Pro retina display) and although better there were still some bit errors.

I saved the files, reformatted the cards, and they seem to work just fine; no permanent damage.

It looks to me like the effect of a large magnetic field that randomly reassigned bits of data. The thing is, I don't have any idea where this type of magnetic field came from. I checked and it doesn't seem like MRI is used in airport security.

The loss is not major; it was just my daughter's soccer team, which is probably the most photographed team in the National Premier League. And it wasn't a particularly important game; just a college recruitment showcase. That said, I don't want it to happen again. Thinking I should be running dual cards and backing up to multiple media immediately after the event.

Any ideas out there?

Richard

Hmm...I think the only source of magnetic fields would be from the motors that drive the conveyer belt on the scanning machine. I've put my camera and cards through scanners often and never seen a problem, so perhaps there was a malfunction. Dunno. But it's always a good idea to have two copies of anything important on separate media.

jhefti

The no-so-helpful reply I got from TSA, when I inquired about any sources of large magnetic fields:

Thank you for your e-mail regarding the x-ray screening of electronics.

The security screening process will not affect USB devices, Global Positioning Systems (GPSs), hard drives, or any of the data these items contain. Additionally, none of the security screening equipment, including machines for screening checked and carry-on baggage, will affect images or film that have already been processed, such as slides, videos, compact discs, and DVDs.

Please note that large electronics must be removed from their carrying case prior to x-ray screening. Small, portable electronic items and wires, cables, or other connecting equipment associated with any electronic equipment are not required to be removed from carrying cases. However, these items may require removal subsequent to the x-ray screening if the bag’s x-ray image appears to display a prohibited item and a Transportation Security Officer is required to inspect the bag.


We hope this information is helpful.

TSA Contact Center

denisegoldberg

I've traveled by air many times with compact flash cards containing photos. I haven't seen any problems caused by the screening (so far).

I would be very interested in knowing what caused the problem you had, don't suppose you'll get an answer though.

--- Denise

jhefti

denisegoldberg wrote: »

I've traveled by air many times with compact flash cards containing photos. I haven't seen any problems caused by the screening (so far).

I would be very interested in knowing what caused the problem you had, don't suppose you'll get an answer though.

--- Denise

I certainly won't find out from the TSA!

I fly all the time, but can't remember any time that I carried fully loaded CF cards with me through security. Usually they live in my camera suitcase, and I almost always download during or right after a shoot.

I am going to try putting a loaded card into an MRI machine, which I have access too, just to see what happens.

kdog

John, I'm not certain from your description. But... It seems to me the common denominator here may be your card reader. Did you happen to try a different one before reformatted the cards? Did you try reinserting the cards back into the cameras to see if the picture review worked there?

Richard

kdog wrote: »

John, I'm not certain from your description. But... It seems to me the common denominator here may be your card reader. Did you happen to try a different one before reformatted the cards? Did you try reinserting the cards back into the cameras to see if the picture review worked there?

Good questions, Joel. Thinking about it again, a magnetic field would have to be strong enough to induce a current in the cards to alter the content--they're less sensitive than magnetic disks. This seems pretty unlikely even if something is malfunctioning in the screening equipment. The image you posted does not show random corruption--there's clearly a pattern there to the rows. So a problem with the reader (or its cable) seems like a better explanation.

Sam

John,

I went to your website and must say, you really have a nice camera. rofl

Seriously, great work.

I have experienced similar issues when downloading to my old PC laptop, but the real culprit was the file transfer not the file its self. It had something to do with the card reader.

Should this happen again I would recommend putting the card back into the camera ans see if the previews are intact. If all looks good try downloading using a different card reader and a different computer.

If you download the files using the same card reader and the issue is the card reader, all will get is corrupted files to analyze.

I used to take a cheap usb card reader in my lap top bag. Now I take my firewire 800 reader I have on my desktop and haven't had any issues.

AS for the TSA.....................Depending on who you communicate with they may or may not have a clue with regard to any questions, or policies you ask about. They may tell you the truth, outright lie or
just read the party line.

It will be interesting to see if an MRI machine can corrupt a card. I am putting money down that it can.

Sam

jhefti

kdog wrote: »

John, I'm not certain from your description. But... It seems to me the common denominator here may be your card reader. Did you happen to try a different one before reformatted the cards? Did you try reinserting the cards back into the cameras to see if the picture review worked there?

Good thought...My daughter also suggested I look at this issue. The card reader is a fairly new Lexar UDMA7 reader, but I have used it many times with no issues. In fact, I shot a basketball game yesterday and it worked fine. Still, it is the common denominator as you say.

One this I didn't mention is that when I put one of the corrupted cards into the camera, the camera gave me an error message that it did not recognise the card, suggesting that there was in fact something wrong with the card (and odd because it had been formatted for the body). I then formatted it and it worked fine.

jhefti

Sam wrote: »

John,

I went to your website and must say, you really have a nice camera. rofl

Seriously, great work.

I have experienced similar issues when downloading to my old PC laptop, but the real culprit was the file transfer not the file its self. It had something to do with the card reader.

Should this happen again I would recommend putting the card back into the camera ans see if the previews are intact. If all looks good try downloading using a different card reader and a different computer.

If you download the files using the same card reader and the issue is the card reader, all will get is corrupted files to analyze.

I used to take a cheap usb card reader in my lap top bag. Now I take my firewire 800 reader I have on my desktop and haven't had any issues.

AS for the TSA.....................Depending on who you communicate with they may or may not have a clue with regard to any questions, or policies you ask about. They may tell you the truth, outright lie or
just read the party line.

It will be interesting to see if an MRI machine can corrupt a card. I am putting money down that it can.

Sam

I think this is a good suggestion. I hadn't really thought about the card reader until my daughter (not a photog) suggested it. I have had problems with cheap card readers in the past, but always of a binary nature: they worked fine or they didn't work at all.

I should mention that a couple of the pins did get bent in this reader a few weeks ago, but I straightened them and it seemed to work fine afterwards until this past weekend.

Regarding the TSA, they just sent me the form response I posted above. They don't have a clue, and it's not worth the bother to try to find out. I was thinking maybe they were trying out an MRI system to determine the nature of liquids; something I know they are experimenting with. Given that it's LAX and all, I thought perhaps they were alpha-testing an MRI unit and they might actually tell me! rofl

Thanks for the kind words about my camera

kdog

jhefti wrote: »

One this I didn't mention is that when I put one of the corrupted cards into the camera, the camera gave me an error message that it did not recognise the card, suggesting that there was in fact something wrong with the card (and odd because it had been formatted for the body). I then formatted it and it worked fine.

Oh, that does indeed sound like the cards got corrupted then. That's a shame.

jhefti

Yeah, it's really weird. None of my fellow shooters have heard of this happening.

Just glad it was not some major event I was shooting; then again, I'd have been a lot more careful and compulsive in backing up if it were!

ian408

It's very unlikely MRI would be used as an airport screening mechanism. There are two many potential pitfalls. Metallic objects, including medical implants (joint replacement, screws, aneurism clips), make up (sometimes contains metallic powders), and credit card stripes are just a few things that would preclude it's use. MRI also requires a transmitter/receiver coil surround the sample. Which doesn't mean there were not strong magnetic fields present. If there were, I would expect you would have credit card stripe issues as well as laptop issues. I would also expect your images to be unrecognizable, or nearly so.

I'm in the card reader camp also. Aside from the images, you said you up/down loaded other things that had problems.

I suppose the other thing to ask is whether you always format the cards in the camera you will be using them in, or do you format them using the reader, or could they have been formatted in another camera? I generally want to format my CF cards in the camera I will use them. It also sound like you may not always format the card (finding more than what you believed to be on the card) every time you use it. I would suggest a workflow that includes re-formatting the cards before use and downloading the cards to your laptop and a backup device as soon as is practical after use.

Sam

I may have discovered the problem!!!!!!

The Lexar card mentioned by the OP looks like a fast UDMA 7.

I was researching USB 3, firewire, and eSATA connections to get a faster transfer of images from my CF cards to my computer.

When I spoke with Lexar the tech guy told me to make sure I got a card reader that was compatible / rated for UDMA 7. He stated if you use the UDMA 7 cards in an earlier reader that wasn't designed / built for the new UDNA 7 cards it will cause a problem.

They found that the card readers would seem to work fine, but after time, could be several months, the new UDMA 7 cards will fail.

Hows them apples!!

New card reader is on the way.

Sam

jhefti

Ian408: Apparently there is an effort to develop an MRI system that doesn't use very strong magnets, mostly for the purposes of seeing what kinds of liquids are present in baggage that's put through screening. It's only in the development stage, so I doubt this is the issue. My cards went through the x-ray machine in my carry on bag, as did my wallet with my credit cards. The credit cards are fine.

I do format my cards before each shoot, in the cameras in which they will be used. What I noticed when I put the two corrupted cards back into their respective cameras is that the camera gave me an error message that it could not recognize the cards. However, I re-formatted them and they now work fine. (Shot two games since then without problems.)

I also usually download during the assignment, or immediately afterwards. This past Sunday I was in a real rush to get to the airport, so I just pulled the cards and put them in my computer bag to download later.

What I did try to do at the airport was to check the ability to upload images from my computer to the card, then download back to the computer. When I did this I noticed some corrupted files but still recognizable as photos. However, if the partition on the cards was corrupted, this might happen.

Sam: I was using the latest Lexar UDMA7 card reader, in part because I had a Lexar card fail completely and permanently a few months ago (at a big event). The tech guy at Lexar told me the same thing, so I bought the updated reader. And anyway, when I'm on assignment and submitting live I like the extra speed of a UDMA7-compatible reader. (Not sure I fully buy Lexar's story; poor engineering in any case.)

Anyway, thanks for the suggestions. Still trying to figure this out, though there's a good chance I won't.

ian408

That scanner is more NMR like (NMR and MRI are the same thing-MRI is just "friendly") and meant to scan bottles and not bags. NMR is used extensively to identify chemical compositions. In fact, some wineries explored its use to reproduce very old wines. Cool technology.

FlyNavy

I am an airline pilot and always carry my point and shoot with me at work. I go through X-ray screening at least 10 times a month and have never had any problems.

Sam

John,

My understanding is that it's an issue with the UDMA 7 regardless of the manufacturer. I ordered a eSATA card to USB 3 and a new UDMA 7 compliant card reader so I should not only be safe but speedy.

I am on a Mac and they don't have USB 3 ports, yet all the new card readers and many other peripherals are USB 3. Sure I could use the USB 2 port but that's not what anyone would call speedy.

Sam

Sam

FlyNavy wrote: »

I am an airline pilot and always carry my point and shoot with me at work. I go through X-ray screening at least 10 times a month and have never had any problems.

I would worry when you start glowing at night.

Sam

jhefti

ian408 wrote: »

That scanner is more NMR like (NMR and MRI are the same thing-MRI is just "friendly") and meant to scan bottles and not bags. NMR is used extensively to identify chemical compositions. In fact, some wineries explored its use to reproduce very old wines. Cool technology.

Yes, of course you are right! I should have chosen my terms more carefully. NMR usually has a fixed sample chamber and this does not need a spatial image of the subject being tested. MRI is NMR with spatial information. In any case, I doubt either of these were at play...

jhefti

Sam wrote: »

John,

My understanding is that it's an issue with the UDMA 7 regardless of the manufacturer. I ordered a eSATA card to USB 3 and a new UDMA 7 compliant card reader so I should not only be safe but speedy.

I am on a Mac and they don't have USB 3 ports, yet all the new card readers and many other peripherals are USB 3. Sure I could use the USB 2 port but that's not what anyone would call speedy.

Sam

Ah, I see...Yes, I just bought the Lexar reader, as I thought this is what the tech guy told me to do. I guess I should also buy the eSATA-to-USB3 card as well.

jhefti

FlyNavy wrote: »

I am an airline pilot and always carry my point and shoot with me at work. I go through X-ray screening at least 10 times a month and have never had any problems.

I don't fly as much as you, but close. I've never had this problem either.

It could just be a coincidence that the problem happened at an airport.

Sam

UPDATE:

I have spoken with two different tech reps at both SanDisk and Lexar.

I found all to be knowledgeable and telling a consistent story.

SanDisk says no problem with using older card readers with the newer UDMA 7 cards.

Lexar says yes there is a problem. They base their claim on both personal experience and customer feed back.

The theory seems to be the speed difference between the fast card and the slower card reader results in errors. These errors are small and go unnoticed until a certain point where the errors create a condition where the card is no longer recognized in the camera or the older card reader. The fix seems to be to use a UMDA 7 compliant card reader and reformat from the computer. In most cases this will fix the issue, but it can also cause the card to fail permanently.

That's all I got.

Sam

jhefti

Sam wrote: »

UPDATE:

I have spoken with two different tech reps at both SanDisk and Lexar.

I found all to be knowledgeable and telling a consistent story.

SanDisk says no problem with using older card readers with the newer UDMA 7 cards.

Lexar says yes there is a problem. They base their claim on both personal experience and customer feed back.

The theory seems to be the speed difference between the fast card and the slower card reader results in errors. These errors are small and go unnoticed until a certain point where the errors create a condition where the card is no longer recognized in the camera or the older card reader. The fix seems to be to use a UMDA 7 compliant card reader and reformat from the computer. In most cases this will fix the issue, but it can also cause the card to fail permanently.

That's all I got.

Sam

Thanks Sam; that's interesting and confirms my decision to go back to using SanDisk. I rarely use burst mode enough to make use of the small additional write speed. I'll take reliability any day over speed.