function popup(imageName,image_width,image_height) {
  var vertical_padding = 50;
  var horizontal_padding = 36;
  var window_width = image_width + 36;
  var window_height = image_height + vertical_padding;
  var features ='scrollbars=yes,resizable=yes,status=no,top=0,left=0';
  if(window_width > screen.width) { window_width = screen.width - 20; }
  if(window_height > screen.height) { window_height = screen.height - 60; }
  features ='width='+ window_width +',height='+ window_height + ',' + features;
  target = window.open(imageName,'',features).document.bgColor="rgb(34,70,79)";
}