Image resolution in Dynamic Carousel

I'm having problems solving the images that come inside the carousel, how can I set a default for css or javascript? follows images

followmyaspxcode:

<divid="paginas">
        <div class="sliderFrame">
           <div id="slider">
                <asp:PlaceHolder runat="server" ID="phFotos"></asp:PlaceHolder>

            </div>
        </div> 

* I did not load the tags

.CS:

public partial class ImovelDetalhe : System.Web.UI.Page
    {
        private ImovelBo _imovelBo;

        protected void Page_Load(object sender, EventArgs e)
        {

            if (!IsPostBack)
            {
                carregarInformacoes();
            }
        }

        private void carregarInformacoes()
        {
            int codigoImovel = 0;
            Int32.TryParse(Request.QueryString["CodImovel"], out codigoImovel);

            _imovelBo = new ImovelBo();
            var imovel = _imovelBo.ObterDetalhe(codigoImovel);

            if (imovel != null)
            {
                lblDescricao.Text = imovel.Descricao;
                lblOperacao.Text = imovel.Operacao;
                lblCidade.Text = imovel.Cidade;
                lblLocalizacao.Text = imovel.Localizacao;
                lblTipoImovel.Text = imovel.Tipo;
                lblQtDormitorios.Text = imovel.QntDormitorio.ToString();
                lblValor.Text = imovel.Valor.ToString("#,##0.00");

                if (imovel.Fotos != null)
                {
                    foreach (var item in imovel.Fotos)
                    {
                        Image foto = new Image();
                        foto.Width = 700;
                        foto.Height = 306;
                        foto.ImageUrl = item;
                        phFotos.Controls.Add(foto);
                    }
                }
            }
        }
    }
}

* I noticed the sizes here anyway, it did not work out  I wanted to leave it something like this:

Thank you very much