function ShowDocument(ima)
{
	myImage = new Image();
	myImage.src = ima;
	var wid = myImage.width;
	var hei = myImage.height;
	if (wid != 0 && hei != 0) 
	{
		opts = "scrollbars=no"
		var top = (screen.height - hei) / 2
		var left = (screen.width - wid) / 2
		
		if (top < 0)
			top = 0;
			
		if (left < 0)
			left = 0;
		
		if (wid > screen.width)
		{
			wid = screen.width;
			opts = "scrollbars=yes"
		}
		
		if (hei > screen.height)
		{
			hei = screen.height;
			opts = "scrollbars=yes"
		}

		window.open ("../preview.asp?source=" + ima + "&largo=" + wid + "&alto=" +hei, "", opts + ",resizable=yes,width=" + wid + ",height=" + hei + ",top=" + top + ",left=" + left + ",status=no,location=no,toolbar=no");
	}
	else
	{
		ShowDocument(ima);
	}
}