When did Vader lose his chest plate?

I just noticed this whil watching ROTJ, when Anakin and Luke are finally face to face, his chest plate is completly gone!!! All these years I never noticed that detail. When did they remove it? Was that his breathing apparatus then? You can lock as soon as my questions are answered, LOL!!

 

I can still see it. What version are you looking at?

 

Widescreen version DVD, look at the scene when Anakin expires and Luke places him down, it's gone, no joke!!

I rewinded, FF who knows how many times, but it's ggg gone!!!

As a matter of fact, when Luke is cradling him, right after Anakin destroys the Emperor, it's obvious that the chest plate is not to far below his collar bone area, now FF to the scene in question...

 

Depends what piece you mean

[image=http://www.petridish.net/pics/19662/Vader.jpg]


Assuming you mean the lower piece pointed to in the picture...


[image=http://www.petridish.net/pics/19662/vader1.jpg]
This shot doesn't really show it, but it's hard to tell from the distance

[image=http://www.petridish.net/pics/19662/vader2.jpg]
This is as low as the camera ever travels during the exchange, and the box is definitely hanging lower than that

[image=http://www.petridish.net/pics/19662/vader3.jpg]
Here you can see a slight rise where the box should be, but it's unclear whether it's the box or his folded arms