I bought a Canon 850. When I bought it, the clerk said that the card of 1G could record for 45 minutes, but now I can record for 9 minutes at most? Why?

Don't talk nonsense if you don't understand upstairs.

1 850 At the highest accuracy, the card of 1G can record a short film for about 8 minutes, but if it is set to the most compact mode, it can shoot for more than one and a half hours, of course, the quality is almost impossible to watch. The clerk said that 45 minutes is the time for filming in the middle file. He didn't explain it to you clearly, which is a bit cunning! There is nothing wrong with your card. If you don't believe me, you can check your camera manual, which is described in detail on page 135 of a thick advanced guide.

2. The shooting content is completely stored in the SD card. Most digital cameras have no memory, and some models do have built-in memory, but they are equipped for emergency use, and the size is basically between 16-32m, which is only enough to store about 10 photos, not to mention short films. 850 has no built-in memory.