A recent Canon patent application (Pub. No.: US 2008/0025574 A1) reveals the next step in digital watermarking - Iris Registration.

The short and sweet of it?

1. Turn the Mode dial to “REG”
2. Choose between “REG 1″ through “REG 5″ (for up to 5 registered users)
3. Put eye to viewfinder
4. Look at display of center distance measurement point
5. Press the shutter button
6. Iris image captured
7. Go shoot

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