Damaged JPG?

For the first time I was using RAW+JPG (largest size of both). Of around 50 photos, I found that probably 80% of the jpg files were "damaged".

The lower 1/2 to 2/3 of the photo was a single solid color (primary and complementary). There were also 3 fine lines above this color (similar colors). The top of the photo looked OK.

In a few of the photos the bottom was not solid. The left 20% of the photo was shifted right to the center of the photo but was dim as it was "overlaid" by the solid color.

The RAW files were fine.

I shot these with a 5dii using the same Sandisk card I normally use. I copied the photo's as I always do with a card ready and viewed them in Bridge.

Interestingly when I opened the photos in Photoshop I received the following error message: "The document may be damaged (the file may be truncated or incomplete)"

Just for completeness (although I don't think this matters) the photos were shot under compact fluorescent light at 1/60 sec exposure using a custom set white balance. At first I thought this might be the problem but the exposure should have been OK even for regular fluorescent lights and it should not matter for the CFL and the message from Photoshop seems to indicate that the actual file is bad. Also the photo's were taken using a Canon remote release and not taken rapidly (once every minute or so).

I tried to repeat this and all of the next 100 jpg's were fine.

Anybody ever see this or have an idea what the problem might be?

post a sample? Most likely a card problem.

Format the card and start again.
Happens!
Hope the shots weren't going to win you 'Photographer of the Year 2010'

I've had similar problems and have actually watched it happen while PP. I've posted several questions with no real answers. I sent the camera in to Canon and they replaced one of the processors (I think to CYA if nothing else). Still happens. I don't believe it's happening in camera but somewhere in the copy/rename process. Very annoying.

I'd agree that it seems most likely a memory card problem. Have you tried another?

KCMO Al wrote in post #9595433
I've had similar problems and have actually watched it happen while PP. I've posted several questions with no real answers. I sent the camera in to Canon and they replaced one of the processors (I think to CYA if nothing else). Still happens. I don't believe it's happening in camera but somewhere in the copy/rename process. Very annoying.

This is file corruption and it usually happens if the memory card in the camera is going bad. If it is happening to you on your computer then it could mean that your hard drive or RAM is going bad.

I had the same problem right before a card went out on me. The best thing to do is switch to a different card and pitch that one in the trash. After the card went out, and I switched to another one, I didn't have this problem any more. When I had the problem, formatting the card did not help, either formatted with the computer or the camera. I tried the card in three bodies, and it still was no good.

Best to pitch it now and use a different card.

I can't rule out the memory card, but the fact that only the jpg files are damaged not the raw files seems to point to something else.

The jpg files were written automatically with the raw files and all of the photos were taken over a two day period.

I am worried that it is the camera but I have taken lots of combination raw/jpg shots and then lots of raw only shots since the problem happened and have had no problems.

It might have been the transfer to disk but again why only the jpg files. Unfortunately I deleted the files on the card (and reused the card) before I realized that the jpg files were bad.

ToyTrains wrote in post #9595995
I can't rule out the memory card, but the fact that only the jpg files are damaged not the raw files seems to point to something else.

Just speculating here but it is possible that the RAW file format is better able to handle corrupted data midway through the file. With a .jpg file if one bit is off it throws off everything after that, which is why so much of the image is messed up. It could be that with the raw file format having a corrupted bit of data just means that one pixel is messed up and would simply be "lost" as if it were a bit of noise.

The easy answer is to try a different card - if the problem repeats, you know it's not the card; if the problem doesn't repeat, then mostly likely it was the card.

ToyTrains wrote in post #9595995
I can't rule out the memory card, but the fact that only the jpg files are damaged not the raw files seems to point to something else

I don't understand your attitude. Have you loaded the raw data of such a damaged file and viewed it in 100%? Do you get a proper image? If yes, then there can be no question, the embedded JPEG is damaged. This is the question of luck: there is or there are erroneous location(s) on the card, and depending on what gets written on that location(s), the damage may be in the preview, in the raw data, or in something else.

Put the card in your card reader/writer and format it in Windows with verification (this only for test; I would throw it away even if it said that there is no more error).

I had this happen moving files from one drive to another. I was getting write caching errors due to a USB hub issue (power I think). Anyway, about 10% of the images had this problem .. good job I had backups

Perfect_10 wrote in post #9597137
I had this happen moving files from one drive to another. I was getting write caching errors due to a USB hub issue (power I think). Anyway, about 10% of the images had this problem .. good job I had backups

I am hoping it is the card reader, I might try just copying files over and over to see if any fail. Fortunately the raw versions of the photos were fine so that was my backup.

I was shooting with jpg to make it easier for my wife to use the shots without me having to go through raw conversion. So much for that.

krb wrote in post #9596729
Just speculating here but it is possible that the RAW file format is better able to handle corrupted data midway through the file. With a .jpg file if one bit is off it throws off everything after that, which is why so much of the image is messed up. It could be that with the raw file format having a corrupted bit of data just means that one pixel is messed up and would simply be "lost" as if it were a bit of noise.

The compressed DNG data is roughly in the same format as the JPEG data (though the DNG is lossless). Both formats are very sensitive to errors. I had such errors in the embedded preview, which is JPEG; it looks somewhat different, because Canon cameras organize the JPEG preview in two or three columns, but in essence that is the same.