thats how I came across the problem in the first place. I was using the QXD solely not taking as many pictures as to fill the QXD up!! Little did I know that it was set up in backup mode so the pics I took were already on CF. When I forgot to put the QXD in and took some pics they automatically wrote to the only card available which was the CF. On reading the CF thats when I found the other images and noticed the difference in quality from the XQD.