title: Using numpy.random.normal
body: <p>I have this code, which is part of a bigger code. </p>
  
  <pre><code>newimg = pf.getdata(name)
  print newimg
  newhdr = pf.getheader(name) 
  normalNoise = np.random.normal(0,poisson)
  test = newimg + normalNoise
  </code></pre>
  
  <p>pf is "pyfits" and "name" is the name of a .fits file that I read in. I want to take that .fits file and add noise to it in such a way that the amount of noise is randomly distributed among all the pixels. I would like to be able to add a greater amount of noise for a greater amount of standard deviations; in other words, the image should become less and less discernible as I increase the value of the variable "poisson." How do I go about doing this? </p>