title: Changing navigation bar back button image size globally
body: <p>Currently I am using the following code to produce a custom back button image for my navbars:</p>
  
  <pre><code>appearance.backIndicatorImage = UIImage(named: "arrow-back")
  appearance.backIndicatorTransitionMaskImage = UIImage(named: "arrow-back")
  </code></pre>
  
  <p>Unfortunately my image is large so it looks better on retina devices, and this method just displays the default size.  Any way to shrink it down to get it fitting nicely?</p>
  
  <p><a href="https://i.stack.imgur.com/6VY9Z.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/6VY9Z.png" alt="enter image description here"></a></p>