title: Matplotlib imshow offset to match axis?
body: <p>I'm plotting a bunch of UTM coordinates using a matplotlib.pyplot.scatter. I also have a background air photo that I know matches the extent of the figure exactly. When I plot my data and set the axis I can display the scatter correctly. If I plot the air photo using imshow it uses the pixel number as the axis location. I need to shift the image (numpy array) to it's correct UTM position. Any ideas? I'm fairly new to matplotlib and numpy.</p>
  
  <p>For example: I know that the top left corner of the image (imshow coordinate: 0,0) has the UTM coordinate (269658.4, 538318.2). How do I tell imshow the same thing?</p>
  
  <p>I should also say that I investigated Basemap but it doesn't appear to fully support UTM yet. My study area is very small.</p>