Aperture 3: Darker photos after converting library from Aperture 2 to Aperture 3
When a library created in Aperture 2 is opened in Aperture 3 for the first time, some photos may be much darker than expected.
This may happen to photos that have had the Enhance adjustment brick applied with changes to the Saturation slider but not the Contrast slider. In some cases, Aperture 3 sets the Contrast slider from 0 to 1 during library conversion, resulting in images that look darker than expected.
To fix this issue, move the Contrast slider in the Enhance adjustment brick back to 0 for any affected photos.