If you watch the appendices in the EE, where they show the Lorien scene in Fellowship, and how they turned it from day to night digitally, you'll see Elijah Wood's eyes turn (almost) purple. I had to laugh. Everyone accused him of having his "eyes digitally enhanced" and he laughingly denied it-- but (in this case) it was true; only it was all done after the fact by the editors turning day to night.
There's an explaination, of course. When (in RL) you turn the lights out, your pupils dilate and only the outer rim of your iris is still showing. So your eyes are only showing the very outer rim of color. The outer rim of iris is where the color tends to be darkest (if you have gradations of color in your eyes.) But when a picture (with irises not dilated) is shifted to darker blues, to make it look like night-time, then all that lighter colored iris is still showing-- and you've just turned it much bluer, too.
Most un-natural.
So does that make Elijah a Mary-Sue???

Poor kid.
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