function popup(Link,Name,Width,Height){
  var breedte=Width;
  var hoogte=Height;
  if (breedte==-1) breedte=500;
  if (hoogte==-1) hoogte=500;
  var iMyWidth = (window.screen.width/2) - (breedte/2 + 10);
  var iMyHeight = (window.screen.height/2) - (hoogte/2 + 50);

  var win3 = window.open(Link,Name,"location=no,status=no,menubar=no,scrollbars=yes,resizable=no,width=" + breedte + ",height=" + hoogte + ",left=" + iMyWidth + ",top=" + iMyHeight + ",screenX=" + iMyWidth + ",screenY=" + iMyHeight);
  win3.focus();
}

function popupNoScroll(Link,Name,Width,Height){
  var breedte=Width;
  var hoogte=Height;
  if (breedte==-1) breedte=500;
  if (hoogte==-1) hoogte=500;
  var iMyWidth = (window.screen.width/2) - (breedte/2 + 10);
  var iMyHeight = (window.screen.height/2) - (hoogte/2 + 50);

  var win3 = window.open(Link,Name,"location=no,status=no,menubar=no,scrollbars=no,resizable=no,width=" + breedte + ",height=" + hoogte + ",left=" + iMyWidth + ",top=" + iMyHeight + ",screenX=" + iMyWidth + ",screenY=" + iMyHeight);
  win3.focus();
}