Sigma 70-300mm f4-5.6 DG Macro APO
I've read this lens only does macro from 200mm to 300mm. My question is what happens if you have it switched to macro and go below 200mm, or try to switch it when it's below 200mm. Does it just not focus or will it explode? 
I guess I'm wondering exactly what it is the switch does and if you can easily break it by accident.

