If you plug the phone into a computer and browse the files on it, they're under Phone, Pictures, Camera Roll, with names like WP_20130726_07_56_20_Pro__highres.jpg.
It would be nice to access the high res versions from the device itself. Is there any app that will let you see them? I have Pocket File Manger and that doesn't see them as well unless I missed a setting.
open camera roll
click pic you want to see there
when its on ur screen and under it says open in nokia pro camera under
click that
then ur viewing the high res vers.