You can, but it's kinda slow if you've got more than 10 or so charts. 
  
  
  
Create a javascript function to call this on all of your charts: 
  
getChartFromId("ChartXX").saveAsImage(); 
  
  
  
I also put all of my charts in iframes so when the Flash movie is refreshed by the .jpg, the entire page doesn't reload.