There are a number of different programmed color calibrations available which you might try. You should be able to use Google to find them.
I would suggest that you put this query into the iPhoto and/or Aperture forums. There you will find users who are specifically engaged in issues such as this.
I have a few links that may be of interest to you:
More Like This
- Retrieving data ...
- This solved my question - 10 points
- This helped me - 5 points