var slideShow = {

  imgExt: null,
  photoIndex: 0,
  photos: [],

  start: function() {

    slideShow.imgExt = $('#slideshow_img');

    if (slideShow.photos.length > 1)
      setInterval(slideShow.next, 3500);

  },

  next: function() {

    slideShow.imgExt.fadeOut('slow', function() {

      slideShow.photoIndex = (slideShow.photoIndex + 1) % slideShow.photos.length;

      slideShow.imgExt.attr('src', slideShow.photos[slideShow.photoIndex]);
      slideShow.imgExt.fadeIn('slow');

    });

  }

};


$(slideShow.start);