minimum focus distance

[ketan]

Hi,

I own 70-200 f/4 IS USM. I wish to know what is the use of the first switch (min focus distance)?

Ketan

[dmbpettit]

I have the non-IS version. The switch will change the minimum focus distance. On my the switch toggles between ~1meter and ~3meters (sorry, I don't have it in front of me). Switching it to the 3 meter spot tells the lense not to attempt focusing on things closer than that. I usually leave mine at the 1 meter spot but the 3m spot can help when shooting sports that further away so that your lense doesn't waste time hunting for focus in that range.