[Rolf]

well, I did have my camera.... but not....Some years ago, I was covering the Liffey Swim in Dublin... made meticulous preparations... scouted all my shooting positions, got the right lenses together, tripod, stepladder etc... even cleared 3, 8Gb cards ready for the day... never got a single shot! There were some really great moments that I captured (thought I did!) I was very excited to get back that evening and download the images from three cards....nothing! So, the moral of this is simple... when you empty your images from your cards... DON'T format them on the PC and then put them back in the camera and start shooting! It may appear to save time... but my then 5D saw the cards as corrupted and couldn't record to them... I saw each image as it was taken on the rear screen... but nothing was recorded....

A salutary lesson and one I have never forgotten... I empty the cards... put them in the appropriate body and format in camera... I suspect the same would happen if you borrowed a card from say a Nikon shooter that had been Nikon formatted and it went into a Canon...

Kind regards

Rolf