Often time the image will be taken into Photoshop. One layer will be the original and the second layer will be the eye painted out and made to look closed. Some times cloned from another photo of a closed eye. Then the layered psd is brought into Motion where you can have the second layer just appear where you want it. The effect happens so fast it gives the illusion that the eye just blinked when you just jumped from one layer to the other. People don't expect a super realistic looking blink because they are looking at a still photo that can't blink in real life. Hope this helps and best of luck.
Stephen Smith
Utah Video Productions
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