Cannot Find Files on SD Card on Mac

[jephoto]

actually, Kilrah had the correct answer above. I was deleting the files without knowing that Mac was keeping copies on the card in a hidden folder. I replaced the card and the same thing happened. With a Mac, you need to empty the trash with the card plugged in. Otherwise your card will become completely full when it appears to have no files. New to Mac so I was unaware of this.

Also you can just format the card In the drone. Avoids the hidden file issue.