function menuImage(id, soort) {
  document.getElementById(id).src='site/images/navigatie/' + id + '_' + soort + '.gif';  	
}

function openSlider() {
  if(screen.width){
  var winl = (screen.width-450)/2;
  var wint = (screen.height-380)/2;
  }else{winl = 0;wint =0;}
  if (winl < 0) winl = 0;
  if (wint < 0) wint = 0;
  var settings = 'height=' + 380 + ',';
  settings += 'width=' + 450 + ',';
  settings += 'top=' + wint + ',';
  settings += 'left=' + winl + ',';
  settings += '';
  win = window.open('index.php?pagid=17','fotos',settings);
  win.window.focus();	
}