var Fenster1 = null;
function ShowPhoto (Adresse, width, height) {
  if (Fenster1 != null) // prevent tabbed browsing (don't use an old window with unappropriate size) 
  	Fenster1.close();
  if (ShowPhoto.arguments.length < 4)
	attr="width="+(width+20)+",height="+(height+20)+",scrollbars=no,status=no";
  else
	attr="width="+(width+40)+",height="+(height+40)+",scrollbars=yes,resizable=yes,status=no";
  Fenster1 = window.open(Adresse, "Photo", attr);
  Fenster1.focus();
}