// Slideshow
function startSlideshow (set_pause, set_effects_second, repeat) {

  // default pause, or override
  var pause = 3;
  if (set_pause != '') var pause = set_pause;

  // default effect time, or override
  var effect_seconds = 3;
  if (set_effects_second != '') var effect_seconds = set_effects_second;
  
  // internal vars
  var counter = 1;
  var looping = false;
  var before = 0;

  // pause between slides
  pause = (effect_seconds) + pause;
  
  // play slideshow
  new PeriodicalExecuter(function(slide) {
      
      // appear Image
      new Effect.Appear('slide' + counter, { duration:effect_seconds / 2, from:0.0, to:1.0 });

      if(counter == 0){
        before = repeat - 1;
      }else{
        before = counter - 1;
      }

      // fade Image
      new Effect.Fade('slide' + before, { duration:effect_seconds, from:1.0, to:0.0 });

      // increment counter
      counter++;

      // reset counter / array if limit reached
      if (counter == repeat) {
          counter = 0;
          looping = true;
      }
      
  }, pause);
} // end start slideshow