40D image corruption problem -- Any suggestions

Started Sep 29, 2007 | Discussions thread
Naco Photography New Member • Posts: 2
Re: 40D image corruption problem -- Any suggestions

Guys I believe I found the (real) problem – and the solution to it.

It’s got something to do with the way the CR2 files are written (saved) on the card by the camera, AFTER the USB transfer has been used at least once. You may think it doesn’t make much sense but I have done some intensive tests and it’s confirmed.

1. I did not have this problem UNTIL I used the USB cable for the first time (after about 4000 photos downloaded using the built-in card reader)

2. Once I had the issue I kept the original files on the card downloaded them onto the HDD using both methods: card reader and USB and in both cases the files residing on the card (whether the card placed in the camera or card reader) looked fine – no corruption; the very same files transferred onto the HDD using either method, presented some corrupted files (about 20-30%)

3. I did this very experiment with 2 cards; SanDisk Ultra III 4GB and SanDisk Ultra II 2GB – no difference, same diagnostic.

4. I formatted both cards in camera (not PC) and reinstalled the latest firmware available for Canon 40D (1.08)

5. Shot another batch of about 70 CR2 files using the 4GB card and downloaded then using the built-in card reader – NO CORRUPTION

6. Shot another batch of about 70 CR2 files using the 2GB card and downloaded them using the built-in card reader – NO CORRUPTION

7. Reinserted the 4GB card, formatted it again and shot another batch of about 40 CR2 files but this time I downloaded them using the USB cable – guess what, YES the issue came back again – about 50% of them were corrupted.

8. I reinstalled the firmware again and after shooting another 50 CR2 files I downloaded them using the built-in card reader – if you thing this time they were OK you are perfectly right – NO CORRUPTION.

Conclusion: if you shoot in RAW never transfer your files using the USB port and if you did, then reinstall the firmware and ONLY use a card reader from that point on.
I hope this helps – and it applies to others too.

-- hide signature --
Post (hide subjects) Posted by
T D
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow