As I was watching my favorite part of Revenge of the Sith, where the Emperor kicks Yoda's butt, I once again noticed something that I had been wondering about for quite a while now.

When Palpatine and Yoda jump onto the center podium, and the fight continues, it switches over to the Mustafar fight. After that part, it returns to the Senate battle, however this time, Yoda has his lightsaber, but Palpatine's is gone and he has appeared on a Senate pod high above Yoda.

It doesn't make sense to me that a Sith Lord would just switch off his lightsaber in the middle of a climactic fight. Is there a practical answer to this, or a production measure, or any ideas?