function show_big(imageName,imageWidth,imageHeight,alt) {
var windowWidth = parseInt(imageWidth);// + 4;
var windowHeight = parseInt(imageHeight);// + 26;
var sindex = "win" + Math.round(10000*Math.random());//imageName.lastindexOf('/');
//alert(sindex);
var newWindow = window.open("", sindex ,"width="+windowWidth+",height="+windowHeight+",left= 150, top= 100");
newWindow.document.open();
newWindow.document.write(''+alt+'');
newWindow.document.write('
');
newWindow.document.write('');
newWindow.document.close();
newWindow.focus();
}