$_FILES Array getting empty when using $this->form_validation->run()

When you get to the point of sending 

Code:

$data = array('your_column'=>$variable);

 to the database, do not output the result. Create another $data, for example : $data2 

Code:

$data2 = array('your_column_about_image'=>$variable_for_image);

They both should have the same query name. For example $my_result : 

Code:

$data = array(bla bla);
$this->load->models('My_Backend_Model');
$my_result = $this->My_Backend_Model->lets_insert_form_post($data);

-- dont go if($my_result){} here-- 

start your secont $data2 : 

Code:

$data2 = array(bla bla);
$this->load->models('My_Backend_Model');
$my_result = $this->My_Backend_Model->lets_upload_photo($data2);

 
then run your checking code : 

PHP Code:

if($my_result){
   $this->session->set_flashadata('done','bla bla');
   redirect('somewhere');
}else{
  bla bla
}