title: skimage.io.imsave "destroys" grayscale image?
body: <p>I have an array of graysale image read in from a color one. If I use matplotlib to imshow the grayscale image, it looks just fine. But when I io.imsave it, it's ruined (by an outrageous amount of noise). However, if I numpy.around it first before io.imsave-ing, then it's significantly better, but black and white are still all swapped (dark regions appear white, and bright regions appear dark)</p>
  
  <p>scipy.misc.imsave, on the other hand, works perfectly.</p>
  
  <p>Thank you.</p>