Pixhawk Plane Pics in Vertical

I have set up my rc plane with pixhawk 1 and it works well,

However when on a photogrametry mission it randomly takes pic on the vertical instead of horizontal.
Pic format is 16:09 - Camera Sony Alpha 5100

Any idea?

the carmera has an internal acc and changes the orientation from time to time.
Change the exif value!
i wrote a python script to turn all pictures upright. if you are interested just write me.