title: Magento 1.9.2 - Save custom admin form product new & edit page (custom tab)
body: <p>I achieved to add a custom tab / grid to the product new &amp; edit page with an input field inside. Following this <a href="http://fishpig.co.uk/magento/tutorials/custom-tabs-magento-product-admin/">tutorial</a></p>
  
  <p>The problem is that it's <strong>not saving</strong> the data input. And at this point I have no idea if this is actually not covered in the tutorial or I made a mistake.       </p>
  
  <p>Is this enough to save the data input?</p>
  
  <pre><code>$customFieldValue =  $this-&gt;_getRequest()-&gt;getPost('custom_field');
  
  $product-&gt;save();
  </code></pre>
  
  <p>How could I debug this value in the backend?</p>