diff --git a/skimage/io/collection.py b/skimage/io/collection.py
index e8cc0656..a8a890f4 100644
--- a/skimage/io/collection.py
+++ b/skimage/io/collection.py
@@ -163,11 +163,10 @@ class ImageCollection(object):
             for pattern in load_pattern:
                 self._files.extend(glob(pattern))
             self._files = sorted(self._files, key=alphanumeric_key)
-            self._numframes = self._find_images()
         else:
             self._files = load_pattern
-            self._numframes = len(load_pattern)
-            self._frame_index = None
+
+        self._numframes = self._find_images()
 
         if conserve_memory:
             memory_slots = 1