Ubuntu :: Nautilus Does Not Display Space Taken Up By SD Card?

I have a miniSD card that I use for my BlackBerry. It's 8GB large so I decided to put it in an SD jacket and use it in my camera.

When I plug the SD card into my computer, Nautilus and Disk Usage Analyzer show 1.4 GB yet `fdisk -l`, `df -h` and gparted all show 2.8GB being used.

Code:
$ sudo fdisk -l
{snip}
Disk /dev/mmcblk0: 7969 MB, 7969177600 bytes
221 heads, 20 sectors/track, 3521 cylinders
Units = cylinders of 4420 * 512 = 2263040 bytes

[Code].....

The files shown on the disk are only 1.4GB and my BlackBerry files, yet when I put the disk into my camera, I can see the unaccounted for photos and videos.

I've used gparted to see if there was some unknown/invisible-to-nautilus partition and I can't find one (just as `df -h` says).

I tried doing a `dd` of the entire disk, but that does me no good when I mount the image... it still shows me 1.4GB.

What can I do to see the other files? I'm a computer science undergrad, so you can be as technical as you wish.