// simplified photo pop_up script
function photo_pop(img)
{ 	picfile=new Image(); picfile.src=(img); fileCheck(img); return false;}

function fileCheck(img)
{ 	if((picfile.width!=0)&&(picfile.height!=0))
	{ makeWindow(img); }
	else {
		funzione="fileCheck('"+img+"')"; intervallo=setTimeout(funzione,10); }}

function makeWindow(img)
{ ht=picfile.height+20; wd=picfile.width+20; 
	var args="height="+ht+",innerHeight="+ht;
	args+=",width="+wd+",innerWidth="+wd;
	if (window.screen) 
	{ var avht=screen.availHeight; var avwd=screen.availWidth;
		var xcen=(avwd-wd)/2; var ycen=(avht-ht)/2;
		args+=",left="+xcen+",screenX="+xcen;
		args+=",top="+ycen+",screenY="+ycen+",resizable=yes"; }	
	
	return window.open(img,'photo_pop',args); }

//example link
//<a href='my_big_fat_face.jpg' class='photo_link' onclick='return photo_pop(this.href)'>my_big_fat_face</A>