diff --git a/CHANGELOG.md b/CHANGELOG.md
index 96e027a7a..e6c319637 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,7 +7,7 @@
 - Better handling of tiff files with JPEG compression and RGB colorspace (#503)
 
 ### Bug Fixes
-- Harden updates of the item view after making a large image
+- Harden updates of the item view after making a large image (#508)
 
 ## Version 1.3.2
 
diff --git a/large_image/tilesource/base.py b/large_image/tilesource/base.py
index 3dda88ff7..3563bd17d 100644
--- a/large_image/tilesource/base.py
+++ b/large_image/tilesource/base.py
@@ -132,7 +132,7 @@ def _imageToNumpy(image):
         if not isinstance(image, PIL.Image.Image):
             image = PIL.Image.open(BytesIO(image))
         if image.mode not in ('L', 'LA', 'RGB', 'RGBA'):
-            image.convert('RGBA')
+            image = image.convert('RGBA')
         mode = image.mode
         image = numpy.asarray(image)
     else: