Shoot RAW?Levels in PS? Use your white eyedropper to define the white you want (click on it to set your foreground color and then open the other image and define your white eyedropper in Levels as the color of the foreground. Then adjust Levels with the "white" eyedropper.
-- Emily L. Ferguson mailto:elf@xxxxxxxx 508-563-6822New England landscapes, wooden boats and races, press photography http://www.vsu.cape.com/~elf/