title: Corona Zoom in and zoom back to normal state
body: <p>In Cocos2d I was able to zoom out / scale my scene down, i.e. 0.2, and when i want it restored i could change to 1.</p>
  
  <p>In Corona, if I scale to 0.2, and try and rescale to 1, it keeps it as 0.2, so essentially it takes the arg and scales the current image / displayGroup to that.</p>
  
  <p>So to determine normal scale I need to calculate over scale factor? </p>
  
  <p>Essentially I want to double tap too zoom out, and double tap to return to normal state. But there is no way to hold my previous state and restore that I can figure out.</p>