Originally Posted by WiLL

I think he has a Canon G3 or G5.

ISO is not a mode. The ISO setting allows you to set how sensative your sensor is to light. The higher the ISO, the more sansative it is. However on most point and shoots, once you get into really high ISOs, you start to capture a lot of noise, which you can see in his 3rd pic looking at the darker rolling hills.

http://www.steves-digicams.com/
http://www.dpreview.com/