Resize
            proxies in the Source Area individually or as a group. You can reduce
            the size of proxies if your Source Area contains many clips, or
            enlarge a selected few that you might want to compare.
         
         To resize a Source Area proxy:
         
         
            - While holding down Alt, grab any side or corner of
               the proxy with the cursor and drag it. An indicator on the proxy
               displays its current size.
            
To resize a group of Source Area proxies:
         
         
            - Select the clips that you want to resize.
               See 
                        Selecting Clips.
            
- While holding down Alt, grab a side or corner of the
               current source clip (green border) and drag it.
               When you let go of the
                  resized clip, the selected clips are resized to match it. If the
                  focus source clip is not among the clips you select, the most recent
                  focus clip within that selection becomes the current source clip.
                TipYou can also resize
                     Source Area proxies using one of the clip arrangement buttons. When
                     you tile, cascade, or stack clips in the Source Area, all selected
                     clips are resized to match the focus clip.