title: matplotlib equivalent to skimage.io.imread(fname, as_grey=True)?
body: <p>As this is a really common practice... I was wondering is the a matplotlib equivalent to this function in scikit-image?</p>
  
  <pre><code>from skimage import io
  im = io.imread(fname, as_grey=True)
  </code></pre>
  
  <p>To read the RGB file to greyscale directly?</p>
  
  <p>I need to use the matplotlib equivalent because I am using it to plot the result. And as I have observed, it seems the ndarray read by io.imread is not equivalent to that was read by plt.imread.</p>
  
  <p>Thanks!</p>