Importing .DNG via iPhoto; PSE 11 locks photo and requires 8bit conversion before any editing actions are allowed in Full Edit mode.
With image in 8-bit you would be able to access 100% of PSE but with 16 bit the editing is limited and also usage of layers.
Found one nice discussion here on the 16 bit support/difference from PSE perspective. Should be helpful
http://feedback.photoshop.com/photoshop_family/topics/adobe_photoshop_ elements_9_to_10_16_bit_color
Thanks,
Garry
North America
Europe, Middle East and Africa
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