DuracellEnergizer said:

A transient saber that was sacrificed to demonstate the cutting power of assembly line machinery.

God, I hate how unpersonalized and replaceable lightsabers were treated in the PT. Obi-Wan goes through two (or three, if you count Qui-Gon's weapon) before finally getting his signature lightsaber from SW in ROTS (And even then, it's not a film-accurate replica of the SW saber.).

The hilts look basically the same from scene to scene, but there are also differences in the context of the same films. Luke's (Anakin) saber has differences from the ANH one in ESB and even differences from scene to scene in the context of the same movie. Hero (Close up) shots are very few in the context of the films themselves, so it's really no big deal. The main way to spot difference is look at the prop photo books.