Thanks a lot - so your tool would solve both my questions (incl. exposure bias) ! Great !!!
Looking into http://www.sno.phy.queensu.ca/~phil/exiftool/TagNames/Canon.html,
it seems that Canons 5DmarkIII is supported but the 6D is not yet supported.
Do I have to wait for that one ?
I feel a bit stupid not to find a download button or link...
Can you help me !