BRIAN SAYS… EOS cameras take photos without a card so they are ready for in-store demonstration. Early cameras needed a card to work, and the demo capability was added so that shops didn’t need a supply of cards with the cameras. When there is no card, the last picture taken is retained in the camera memory so that it can be reviewed on the LCD screen. Images captured like this are not possible to save to a card or transfer to a computer, and are lost when the power is switched off. In some commercial studios, cameras are permanently connected to a computer for remote shooting. Captured images are sent to the computer to avoid a camera memory card filling up.