function changePhoto(photo_id)
{
    $.getJSON("/category/change_photo/"+photo_id,
        function(data){
            $.each(data, function(i,item){
            
            if(i == 'main_photo_src') 
            {   
                $('#main_photo').attr("src", ''+item);
            }else if(i == 'main_photo_caption')
            {
                $('#caption').html(item)                
            }
            });
        });
}