Stardust wrote:
If you are referring to a SanDisk SD card and if you truly mean 160 or 64 Kb (kilobytes) then that is probably just the space taken by the FAT (File Allocation Table) to keep track of the card file system. If that is the case you can reformat it - you are losing nothing.
With card in computer you can always right click on the SD Card file, then click Properties. That will give you card size, plus free and used space.
And 64 Kb is a very small size for a photo. I would just format the card if that is what you mean.