the natal may be more advanced.. infact yes it is, but the ps eye can do a lot of the same things that it can. Just look at eye pet.
For very basic things like this, yes, both technologies are similar. However, if you wanted to scan yourself into a game, a normal camera like the EyeToy would produce a flat and completely fake looking imagine while the 3D sensor in Natal can produce a 3D model that looks like you. The same is true about scanning objects. When you start to get into more advanced features, the EyeToy is not advanced enough.
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