Problem while retrieving an image from Database

Insert an Image:

OpenFileDialog dlg = new OpenFileDialog();
dlg.ShowDialog(); 

FileStream fs = new FileStream(dlg.FileName, FileMode.Open, FileAccess.Read);                

byte[] data = new byte[fs.Length];
fs.Read(data, 0, System.Convert.ToInt32(fs.Length));
fs.Close();

SqlConnection con = new SqlConnection("server=.\\sqlexpress;Initial catalog=db;Integrated Security=true");
con.Open();
SqlCommand cmd;
cmd = new SqlCommand("insert into img values('" + data + "')", con);           
cmd.ExecuteNonQuery();

Retrieve an Image:

cmd = new SqlCommand("select * from img", con);
DataTable dt = new DataTable();
SqlDataAdapter da;
da = new SqlDataAdapter(cmd);
da.Fill(dt);
byte[] MyData = (byte[])dt.Rows[0]["Images"];
MemoryStream stream = new MemoryStream(MyData);
pictureBox1.Image = Image.FromStream(stream);

CREATE TABLE [dbo].[Img](
[Id] [int] IDENTITY(1,1) NOT NULL,
[Images] [image] NULL
) 

Error:

While inserting an image no error.

But while retrieving an image "Parameter is not valid." error came.

Can anyone Pls give the soln.

Thanks in Adavance.