Empty the camera roll but still consume large storage?

I had no space on my iphone 5 16G ,so i decided to empty My camera roll . I connect the iphone to my pc and delete all my photos exists in (DCIM Folder)except 100 .

When i check the size of (DCIM Folder) After deleting there is about 140 mb however when i check the storage i found about 2.2 Gb !! i try to restart and update it to IOS 8.1.3 but in vain ,the same storage . Are there more hidden photos ?and how to find them ?