From 02cd903119fa2ff39cb60aaae65d1aad2eb625d5 Mon Sep 17 00:00:00 2001
From: Shannon Osborne <sosborne@stsci.edu>
Date: Thu, 30 Aug 2018 09:43:18 -0400
Subject: [PATCH 1/3] Shift distorted PSFs back to correct detector position

---
 webbpsf/distortion.py | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/webbpsf/distortion.py b/webbpsf/distortion.py
index 6785a700..cad205c3 100644
--- a/webbpsf/distortion.py
+++ b/webbpsf/distortion.py
@@ -119,6 +119,10 @@ def apply_distortion(hdulist_or_filename=None, fill_value=0):
     xnew += xpix_center
     ynew += ypix_center
 
+    # 5) Shift the new indices so the center matches the sci indices
+    xnew += np.mean(xsci) - np.mean(xnew)
+    ynew += np.mean(ysci) - np.mean(ynew)
+
     # ###############################################
     # Interpolate from the original indices (xsci, ysci) on to new indices (xnew, ynew)
     # noinspection PyTypeChecker

From aa189bdf3cde8dbee63f8dbd8eea491c5964cb35 Mon Sep 17 00:00:00 2001
From: Shannon Osborne <sosborne@stsci.edu>
Date: Thu, 13 Sep 2018 15:28:45 -0400
Subject: [PATCH 2/3] Update fix for distorted PSFs off from detector position

---
 webbpsf/distortion.py | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/webbpsf/distortion.py b/webbpsf/distortion.py
index cad205c3..4a06671c 100644
--- a/webbpsf/distortion.py
+++ b/webbpsf/distortion.py
@@ -101,6 +101,10 @@ def apply_distortion(hdulist_or_filename=None, fill_value=0):
     # Going from Idl to Sci this way allows us to add in the distortion
     xsci, ysci = aper.idl_to_sci(xidl, yidl)
 
+    # 6) Shift the sci indices so they match the PSF's position again (moved slightly off from pysiaf calculation)
+    xsci += xpix_center - np.median(xsci)
+    ysci += ypix_center - np.median(ysci)
+
     # ###############################################
     # Create an array of indices (in pixels) that the final data will be interpolated on to
     # 1) Set up blank indices (in pixels)
@@ -119,10 +123,6 @@ def apply_distortion(hdulist_or_filename=None, fill_value=0):
     xnew += xpix_center
     ynew += ypix_center
 
-    # 5) Shift the new indices so the center matches the sci indices
-    xnew += np.mean(xsci) - np.mean(xnew)
-    ynew += np.mean(ysci) - np.mean(ynew)
-
     # ###############################################
     # Interpolate from the original indices (xsci, ysci) on to new indices (xnew, ynew)
     # noinspection PyTypeChecker

From 0c79dd300a1528d2d8f60e18fa3d37e909b1fb8e Mon Sep 17 00:00:00 2001
From: Shannon Osborne <sosborne@stsci.edu>
Date: Mon, 22 Oct 2018 17:21:02 -0400
Subject: [PATCH 3/3] PEP8 update

---
 webbpsf/distortion.py | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/webbpsf/distortion.py b/webbpsf/distortion.py
index 75293731..89d56205 100644
--- a/webbpsf/distortion.py
+++ b/webbpsf/distortion.py
@@ -1,14 +1,12 @@
-import copy
-
 import astropy.convolution
 import astropy.io.fits as fits
+import copy
 import numpy as np
+import poppy
 import pysiaf
 from scipy.interpolate import griddata
 from scipy.ndimage.interpolation import rotate
 
-import poppy
-
 
 def _get_default_siaf(instrument, aper_name):
     """ Store the default SIAF values for distortion and rotation """