function zoom_image(img, max_w, target){
 	var zoom_el=make_el(target);
	var img_el=new Image()
	img_el.src=img;
	var img_str=""
 	img_str+="<img class=\"normal_cx\" src=\""+img+"\" width=\"0\" height=\"0\" ";
 	img_str+="onload=\"this.img=new Image(); this.img.src=this.src;this.dim=zoom_max_w('"+max_w+"',this.img.width,this.img.height);this.width=this.dim[0];this.height=this.dim[1];\">";
 	zoom_el.innerHTML=img_str
}
function zoom_max_w(max_w,img_w,img_h){
  var dim=new Array()
	var a_r=img_h/img_w
	if(img_w>max_w){
		img_w=max_w;
    img_h=img_w*a_r
	}
  dim[0]=img_w
	dim[1]=img_h
 	return dim
}