• To zoom in for a closer view of the 
   image, press the Option key while 
   you click in the sample.

• To zoom out to a reduced view of 
   the full image, press Shift-Option 
   while you click in the sample. 
   (This may be unavailable if the 
   image is very large.)

• To move to a different part of the 
   image, press the Command key 
   while you drag inside the sample 
   to display a different portion.