function add_shot(shot_id)
{
  var value = $('input_'+shot_id).value
  new Ajax.Request('/related_shots/update/'+shot_id+'/'+value, { method: 'get' });
  return false;
}

function remove_shot(shot_id)
{
  new Ajax.Request('/related_shots/update/'+shot_id+"/nil", { method: 'get' });
  return false;
}