Google Maps API v3 base map visibility

Is it possible to changr visibility or opacity of google base map ? I am adding it like in simple example, and adding data layer as overlay and want to see only vector markers. Is it possible?

var map;
function initialize() {
  var mapOptions = {
    zoom: 8,
    center: new google.maps.LatLng(-34.397, 150.644)
  };
  map = new google.maps.Map(document.getElementById('map-canvas'),
      mapOptions);
}

google.maps.event.addDomListener(window, 'load', initialize);