After transferring the images to my computer, several files from more than one card are showing as corrupt. I have never had this before. I’m using a Canon 50D which is less than a year old, I have tried transferring the files by connecting the camera and by putting the card in a reader – both get the same result.

However, if I open the image straight from the card without importing it first, it appears to be okay.

Now I notice some pictures are missing altogether. Basically, I shot around 150 couples in a formal pose as they made their way into a dinner dance function. Whilst processing, I realized someone was missing; the event organizer, who is also my wife’s father! I knew I had photographed him right at the beginning, so I got out a copy of SanDisk’s RescuePro and ran it on the offending card. I found about eight images which were in the original transfer.

If it was one image, I could imagine having deleted it by mistake (not easy to do by accident, though). If it was a set of images from the very beginning of using the card, I could – at a real stretch – imagine that I had formatted the card without thinking (not that likely). But the missing images are a small group from within the middle of the card. I would have to have deleted eight images one after another and, apart from the sequence you go through to delete individual images, I just would not have had the time during the shoot.

I’m thinking there must be some kind of issue either with the card, the camera (firmware version) or a combination of the two. Does anyone have any thoughts on this, or had similar (or other!) experiences with other makes of card?

Camera: Canon EOS 50D firmware version 1.0.3
Card: SanDisk Extreme III 4Gb CF (brand new, unused)