Do you know how I can determine what that is? WAIT: HOLD THE PRESS! I typed that and then grabbed my camera, put it on 'underwater' mode and macro, then half-pressed the shutter when I had an item to actually focus on and the GREEN BOX appeared! Then I tried to focus on my mouse pad (all black) and NO BOX! Please don't give me TOO much grief about not knowing what the green box is. I saw people referring to it in this thread and thought my camera didn't have it!!!!! Doh! Now I'm 'assuming' this is the 'smallest focus spot' my camera allows? (No, I haven't taken any classes - why do you ask?! Duh!).
Final excuse ... like most people my age, I have to use readers. I did get my masked updated with my new script for near and far vision, but it's still not optimal. I wish I could take a pair of readers down there with me!