Corrupted CR2 file out of the camera

[groman]

I have a 7dii bought new 6 months ago- I have gotten three or four files that came off the camera corrupted. Why is this happening and should I worry about it? So far it hasn't seemed to affect any important shots, but I will know I will be dissapointed if it happens to a great shot.

[Ray-uk]

Are you using a full sized SD and not a micro SD with an adaptor.

Are you using a cheap memory card.

Have you formatted the memory card in the camera.

Are you transferring your picture files from your camera via a cable or with a card reader.

[groman]

I am using a Lexar Pro 800x 16gb CF card, and transferring pictures via cable. I have taken about 9,000 pics and only a few have been like this. I can't say I have actually formatted the card- I move all photos from the card to a file folder on the computer, then into Lightroom for processing. The corrupted files show up in the folder after the initial download.

Thanks for getting back to me.

[Ray-uk]

If the files show up as corrupted after you download them but appear alright if you view them on the camera then that suggests you probably have have either a faulty cable or the connection is breaking at times.

I have found that a good quality card card reader is easier and more reliable than using a cable.

The card should be formatted in the camera, the instruction manual tells you that. I would definitely recommend that you format the card in the camera every time after you have downloaded the files and avoid deleting individual files as you shoot.

[ebiggs1]

" I move all photos from the card to a file folder on the computer, then into Lightroom for processing."

If you are using LR as you imply, you need to let LR do all the moving copying and importing.  It is a bad idea to do it outside of LR and then edit in LR.  Let LR do it thing, all its thing.

There are a couple things I am beginning to change my mind or thoughts on.  One is always formatting the SD card in the camera.  I have not seen any problems with doing so with the computer. Maybe just luck but no issues so far.  I will say that I use a Windows machine and not a Mac. If I were using a Mac I would never, never use it to format an SD card for any camera.  Mac's are just too finicky.  Secondly, using a card reader instead of the camera.  I mean cheap card readers that you find at Walmart, etc.  They are terrible and nobody should use one in favor of their camera.

[groman]

Thanks very much- I will try formatting the card in camera. I regularly delet shots directly from the camera- didn't realize it was a bad idea.

[ebiggs1]

"I regularly delet shots directly from the camera- didn't realize it was a bad idea."

They say it is but I have not experienced any issues doing it. 

[Peter]

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@groman wrote:

Thanks very much- I will try formatting the card in camera. I regularly delet shots directly from the camera- didn't realize it was a bad idea.

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It seems to be "fact" without proof. When you delete at file, you just change the address to the file, so it shouldn't give you any problem. With that said also I format the card in the camera after each photo session. Actually even low level formatting the SD card.

Low level formatting the card will decrease the life of the card, but if a card has 100,000 write cycles as a limit, how many years will it survive only by low level formatting each day....

[Peter]

My last failure was 2008. 40D and Transcend. All pictures left on card. Just card error in camera.

2006 I got the whole card destroyed. S3 IS and SanDisk.

[ebiggs1]

It appears the in camera low-level format overwrites the entire card. The normal format just rewrites the system part of the FAT32 partition, leaving data intact. The low level format sets the whole partition data to zero.

I agree it is not good practice to low level format each time since those are write operations and each memory cell on your SD card only has so many writes to it before it becomes unusable. If you decide to format SD cards in your computer, make sure that you check the “Quick Format” and NOT the low level format.