function CargarFoto(img, ancho, alto) {
 movidatemp1=(screen.width-ancho)/2;
 movidatemp2=(screen.height-alto)/2;
 string="toolbar=0,scrollbars=0,location=0,statusbar=0,menubar=0,resizable=1,width="+ancho+",height="+alto+",left="+movidatemp1+",top="+movidatemp2+"";
 fin=window.open(img, '', string);
}