function ImageViewer(url) {
	var w = 100;
	var h = 100;
	var l = 10;
	var t = 10;
	
	if (url_dyn) {
		hWin = window.open(url_dyn + 'ImageViewer.php?item=' + url, '_blank', 'scrollbars=no, resizable=yes, titlebar=yes, status=yes, toolbar=yes, width=' + w + ', height=' + h + ', top=' + t + ', left=' + l); 
		if (hWin) {
			hWin.focus();
		}
	} else alert('Fout: kon ImageViewer niet vinden');
	
}

function PopUp(url, width, height, options) {
	var sw = screen ? screen.width : 800;
	var sh = screen ? screen.height: 600;
	
	var left = (sw - width) / 2;
	var top  = (sh - height) / 3;
	
	options  = 'width=' + width + ',height=' + height + ',left=' + left + ',top=' + top + ',' + options;
	
	var hWin = window.open(url, '', options);
	if (hWin) {
		hWin.focus();
	}
}