Invalid cast from 'System.String' to 'System.Byte[]'.

protected void Button1_Click(object sender, EventArgs e)
{
con = new SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings["DefaultConnection"].ConnectionString );
            
           
cmd.Parameters.Add("@Name", SqlDbType.VarChar).Value = txtName.Text.Trim();
cmd.Parameters.Add("@Description", SqlDbType.VarChar).Value = txtDesc.Text.Trim();
cmd.Parameters.Add("@Image", SqlDbType.Image).Value =txtImage.Text.Trim();
cmd.Parameters.Add("@Active", SqlDbType.VarChar).Value = txtActive.Text.Trim();
cmd.Parameters.Add("@CreatedBy", SqlDbType.VarChar).Value = txtCreatedBy.Text.Trim();
cmd.Parameters.Add("@CreatedDate", SqlDbType.DateTime).Value = txtCreDate.Text.Trim();

cmd.Connection = con;
cmd.CommandText = "sp_SqlImage";

//cmd=new SqlCommand ("sp_SqlImage", con);
           con.Open();
            //cmd.CommandType =CommandType.StoredProcedure;
            cmd.ExecuteReader();

            
            //cmd.ExecuteNonQuery();
            con.Close();
}    

Invalid cast from 'System.String' to 'System.Byte[]'. 
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. 

Exception Details: System.InvalidCastException: Invalid cast from 'System.String' to 'System.Byte[]'.

Source Error: 


Line 78:             con.Open();
Line 79:             cmd.CommandType =CommandType.StoredProcedure;
Line 80:             cmd.ExecuteReader();
Line 81: 
Line 82: