#1: It claims to slow time.
#2: It only slows players and bullets.
What the difference is is simple:
If you fired a bullet with a lifetime of 1.5 seconds with #1, it would continue out of the field after the field ended.
If you fired that same bullet with #2, it would stay around for 1.5 seconds and then end before the field ended.
I hope I explained this well.
Discuss, realize, grumble.