Those are corrupted image files. That can be happening for a number of reasons.
The trick is to trouble shoot the problem and try to identify where the corruption is occuring.
1. Did you format the CF card in your camera? (i.e., not in your computer) It is okay to "wipe" a card by formatting it in your computer, but it should always be formatted again in-camera before using, to insure it's ready for use.
2. If so, you say you have tried a different card with the same results. Is it the same type card, bought at the same time? If they are the same and from the same batch, I might be inclined to suspect bad memory cards. If not the same brand, model and batch, then it's unlikely a memory card problem, particularly if you have used the cards without a problem previously.
3. Have you inspected the cards for signs of camage and the socket in the camera to be sure there are no bent or damaged pins? You might need a flashlight to inspect the pins down in the socket on the camera.
4. If the pins and cards appear okay, do the images appear this way when you review them on the camera's LCD? Or is it only when you view them on your computer?
5. If the images appear this way in on the camera's LCD, have you tried shooting RAW files instead of JPEGs? If RAWs are okay, then I'd suspect that something is causing corruption in-camera when converting the files from RAW to JPEG (all images start out as RAW.... when you set to JPEG they are converted automatically in-camera, according to the processes you have set up in the camera: Picture Style, etc.) If only JPEGs are being corrupted, first try "rebooting" the camera. If that doesn't help, try reinstalling the firmware. If that doesn't help, you'll need to have Canon service look at the camera.
6. If the images are only appearing this way after transfer to your computer (i.e., they look okay on the camera's LCD monitor), then it's more likely the corruption is not any fault of the camera, but is occuring during file transfer. It can be bad connectivity, a bad cable, a bad card reader. I've had files corrupted when a reader was connected via a USB hub, and then transfer just fine once the hub was eliminated and the card reader connected directly to one of the computer's USB ports. If you have changed anything.... are connecting differently for downloads or are using a new card reader... that's the first thing I'd suspect.
I would always try "rebooting" before going to the effort of reinstalling firmware.
If you don't know how to do so, to "reboot" your camera do the following:
1. Turn the camera offf.
2. Remove all batteries... Both the main rechargeable and the little silver date/time/memory battery. You'll need a precision cross point screwdriver to remove the latter. It's in a small "drawer" on the LH side of the camera, near the bottom of the various connectivity sockets and their rubber cover. There is one small screw keeping the drawer in place. Be careful not to misplace the screw after removing it. Depending upon how old the camera is, it might be a good idea to replace the date/time battery, too (it should have approx. a five year life span, depending upon usage).
3. Once all batteries are removed, turn the camera back on.
4. Press the shutter release button once. The shutter won't fire, but this should drain all remaining power from the camera, clearing the memory and resetting factory defaults.
5. Turn the camera off.
6. Re-install the batteries.
7. Turn camera on and check the date/time. You should need to reset it, if you got a proper "reboot". You will likely have to reset any Custom Functions and other menu settings you normally use, too.
8. Test the camera by shooting some images.
If you don't get a proper reboot or the above doesn't help with the problem, you might try everything above again. But this time, instead of pressing the shutter release button, just set the camera aside and leave it turned on for about an hour. This process also should allow remaining power in the circuitry to drain completely and force the camera to reset everything to factory defaults. Once again, checking the date/time to see if it was a successful reboot.
Finally, if none of the above helps, you can try reinstalling the camera's firmware. It could be that some of the instructions it includes have themselves become corrupted and are causing mis-handling of the image files.
Neither rebooting nor reinstalling the firmware is guaranteed to help.... might even be sort of a long shot and unlikely to help. But they are both things you can try yourself at no cost and sometimes one or the other solves a problem.
If neither rebooting nor the firmware reinstallation helps, and you have completely ruled out the possibility that the memory card(s) is(are) bad or that the corruption is happening when transfering the images, you'll have to get the camera looked at. It's probably a failing component.
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Alan Myers
San Jose, Calif., USA
"Walk softly and carry a big lens."
GEAR: 5DII, 7D(x2), 50D(x3), some other cameras, various lenses & accessories
FLICKR & PRINTROOM
