In pictures taken with Canon EOS-450D (probably others), with either negative exposure compensation, or in low enough light that measured EV is negative, exposure compensation and measured EV are both shown as being 2048 too high.
Steps to reproduce:
1) Take a photo with a Canon DSLR, in very low light, or with negative exposure compensation (alternately, see attached picture)
2) Examine Exposure Compensation or Measured EV in a libexif aware program
3) Both numbers should be small and negative, but instead are over 2000
I have attached a patch against canon-mnote-entry.c, that seems to resolve this issue