diff --git a/PIL/TiffImagePlugin.py b/PIL/TiffImagePlugin.py
index 0044c567e..648aa68f0 100644
--- a/PIL/TiffImagePlugin.py
+++ b/PIL/TiffImagePlugin.py
@@ -55,7 +55,7 @@ import struct
 import sys
 import warnings
 
-from .TiffTags import TAGS, TYPES, TagInfo
+from .TiffTags import TAGS_V2, TYPES, TagInfo
 
 __version__ = "1.3.5"
 DEBUG = False  # Needs to be merged with the new logging approach.
@@ -318,7 +318,7 @@ class ImageFileDirectory_v2(collections.MutableMapping):
         """
         Returns the complete tag dictionary, with named tags where possible.
         """
-        return dict((TAGS.get(code, TagInfo()).name, value)
+        return dict((TAGS_V2.get(code, TagInfo()).name, value)
                     for code, value in self.items())
 
     def __len__(self):
@@ -350,7 +350,7 @@ class ImageFileDirectory_v2(collections.MutableMapping):
         if bytes is str:
             basetypes += unicode,
 
-        info = TAGS.get(tag, TagInfo())
+        info = TAGS_V2.get(tag, TagInfo())
         values = [value] if isinstance(value, basetypes) else value
 
         if tag not in self.tagtype:
@@ -503,7 +503,7 @@ class ImageFileDirectory_v2(collections.MutableMapping):
             for i in range(self._unpack("H", self._ensure_read(fp,2))[0]):
                 tag, typ, count, data = self._unpack("HHL4s", self._ensure_read(fp,12))
                 if DEBUG:
-                    tagname = TAGS.get(tag, TagInfo()).name
+                    tagname = TAGS_V2.get(tag, TagInfo()).name
                     typname = TYPES.get(typ, "unknown")
                     print("tag: %s (%d) - type: %s (%d)" %
                           (tagname, tag, typname, typ), end=" ")
@@ -571,7 +571,7 @@ class ImageFileDirectory_v2(collections.MutableMapping):
             values = value if isinstance(value, tuple) else (value,)
             data = self._write_dispatch[typ](self, *values)
             if DEBUG:
-                tagname = TAGS.get(tag, TagInfo()).name
+                tagname = TAGS_V2.get(tag, TagInfo()).name
                 typname = TYPES.get(typ, "unknown")
                 print("save: %s (%d) - type: %s (%d)" %
                       (tagname, tag, typname, typ), end=" ")
diff --git a/PIL/TiffTags.py b/PIL/TiffTags.py
index 3e7aa3613..8fb851cda 100644
--- a/PIL/TiffTags.py
+++ b/PIL/TiffTags.py
@@ -19,6 +19,9 @@
 
 from collections import namedtuple
 
+# Legacy Tags structure
+TAGS = {}
+
 class TagInfo(namedtuple("_TagInfo", "value name type length enum")):
     __slots__ = []
 
@@ -34,7 +37,7 @@ class TagInfo(namedtuple("_TagInfo", "value name type length enum")):
 #
 #  id: (Name, Type, Length, enum_values)
 #
-TAGS = {
+TAGS_V2 = {
 
     254: ("NewSubfileType", 4, 1),
     255: ("SubfileType", 3, 1),
@@ -160,12 +163,17 @@ TAGS = {
     50839: ("ImageJMetaData", 7, 1)
 }
 
+def _populate():
+    for k, v in TAGS_V2.items():
+        # Populate legacy structure. 
+        TAGS[k] = v[0]
+        if len(v) == 4:
+            for sk,sv in v[3].items():
+                TAGS[(k,sk)] = sv
+            
+        TAGS_V2[k] = TagInfo(k, *v)
 
-for k, v in TAGS.items():
-    TAGS[k] = TagInfo(k, *v)
-del k, v
-
-
+_populate()
 ##
 # Map type numbers to type names -- defined in ImageFileDirectory.
 
diff --git a/Tests/test_file_tiff_metadata.py b/Tests/test_file_tiff_metadata.py
index 05aa98bb5..1b5e05b4f 100644
--- a/Tests/test_file_tiff_metadata.py
+++ b/Tests/test_file_tiff_metadata.py
@@ -4,7 +4,7 @@ from helper import unittest, PillowTestCase, hopper
 
 from PIL import Image, TiffImagePlugin, TiffTags
 
-tag_ids = dict((info.name, info.value) for info in TiffTags.TAGS.values())
+tag_ids = dict((info.name, info.value) for info in TiffTags.TAGS_V2.values())
 
 
 class TestFileTiffMetadata(PillowTestCase):