My son returned from a recent trip visiting his father-in-law in Goa from where he had tried to send us some photos, using the services of a Goan internet café. The computer in the café didn't recognise any pictures on the camera even though they were visible on the camera itself. On returning home he tried to download the pictures from the camera card using a card reader but again there were no picture files to be seen even though they were still visible on the camera (an Olympus compact). His brother-in-law had the same experience on the same trip and scanned his camera for viruses when he arrived home where he found numerous trojans etc. lurking. Can Digital cameras pick up computer viruses to make the pictures on the SD card invisible and more to the point can they be transferred to a computer back home.
This was a tale of PC woe but could it happen to our Macs?
If a camera, or any device containing a memory card, is connected to a computer as a "memory device" it will act just like a USB memory stick and could therefore transfer a virus or trojan program.
The issue of the program changing a file type is not unknown, so this is again very likely, but likewise it could be just a misreading of the results by the user due to (for example) a propriety file type.
If I were to write a virus (and I don't because I don't have the skills!), I would probably make it modify file types on a digital camera card so the user would try it in more than one computer, making them think the computer was at fault, therefore spreading the virus more effectively.
At the present, to my knowledge, there is no known virus that effects Macs (Thankfully!).
...Did you manage to get the files out from the Olympus in the end Lionel? Some compacts have an internal memory and will save images to that, rather than saving to an SD card if the menu functions have been altered. It may be a simple case of re-saving the images onto the memory card whilst in the camera itself. This may explain why the pictures were visible on the camera, but not the card and hopefully not the result of a virus. I would be happy to have a look at it if necessary.
Unfortunately when my son came to visit last time he brought the wrong camera and so we were not able to try the various tests that have been suggested to me. However we expect to see him in a few weeks so we shall have a second attempt Thanks for the offer, we will look forward to a visit to Weymouth.