title: imshow a gray image and a binary image python
body: <p>I have a grayscale image and a binary image, and I want to plot them side by side using hstack. It looks like there is kind of adjustment that been made yielding to darken the binary. Anybody faced this problem?    </p>
  
  <p><img src="https://i.stack.imgur.com/oos05.png" alt="enter image description here">    </p>
  
  <p>Here is my code</p>
  
  <pre><code>O = (self.img &gt;= t) * 1
  I = img
  both = np.hstack((I, O))
  imshow(both, cmap='gray')
  show() 
  </code></pre>