function zoom()
{

var shad=document.getElementById("shadow").style;
shad.display='block';
shad.height=(screen.height*2)+'px';
//shad.height='100%';
shad.width=screen.width+'px';
prev=document.getElementById("preview");
wid=(screen.width-800)/2;
prev.style.left=wid+'px';
prev.style.display='block';
}
function closeprev()
{
	document.getElementById("preview").innerHTML='';
document.getElementById("preview").style.display='none';
	document.getElementById("shadow").style.display='none';
}