So. In order to kill somebody with the death note, you have to know his face and name. Let's say, Bob knows both, and wants to kill John. Now he hasn't a picture of John, but he remembers his face and name. But the thing is, that when he met John, John wore contacts, that gave him blue eyes instead of his natural brown eyes.
Now he has to remember Johns face, but John has brown eyes, and he thinks in his mind, that his victim has blue eyes. So does he have to know Johns true eye color?
Interesting, never thought of this. I wonder if we already have some canon material on this topic. At the same time, let's consider this hypothetical scenario:
L has the Death Note.
L meets Near and L wants to kill him because Near stole L's sugar cubes.
L and Near both meet each other and after bidding goodbyes to each other, L writes Near's name on the notebook and schedules his death after 10 hours.
Let's say between that time, Near goes through an eye, an arm and a heart transplantation, which I think is equivalent to Near putting a new pair of clothes and hanging out with Mello, or getting a scar in his face—it's the same according to the Death Note's (Shinigami's) perspective. It wouldn't matter, the person will die.
Another example: Raye Penber also died. He was a detective with different outfits at different times. Raye wrote the names of the FBI agents. The FBI agents (more or less) will be looking different in the present context of Raye Penber writing their names in the Death Note to the time when Raye actually met them (or seen their pictures).
Hope this clarifies it.
