diff --git a/pixelocr/page.py b/pixelocr/page.py
index 76ef924..646a2a8 100644
--- a/pixelocr/page.py
+++ b/pixelocr/page.py
@@ -112,6 +112,22 @@ class Line(PageObject):
         letters = self._combine_diacritics(letters)
         return self._insert_spaces(letters)
 
+    def _optical_correction(self, letter1, letter2):
+        base = min(letter1.top, letter2.top)
+        height = max(letter1.bottom, letter2.bottom) - base
+        bitmap1 = np.hstack([np.ones((letter1.height, 1)), letter1.image.bitmap])
+        bitmap2 = np.hstack([letter2.image.bitmap, np.ones((letter2.height, 1))])
+
+        margin1 = np.zeros(height, np.int)
+        margin1.fill(letter1.width)
+        margin2 = np.zeros(height, np.int)
+        margin2.fill(letter2.width)
+
+        margin1[letter1.top - base: letter1.bottom - base] = np.fliplr(bitmap1).argmax(axis=1)
+        margin2[letter2.top - base: letter2.bottom - base] = bitmap2.argmax(axis=1)
+        margins = margin1 + margin2
+        return margins.min()
+
     def _combine_diacritics(self, letters):
         def is_diacritic(glyph):
             # XXX
@@ -133,9 +149,10 @@ class Line(PageObject):
         for letter, next_letter in pairwise(letters):
             yield letter
             if next_letter is not None:
-                distance = next_letter.left - letter.right
+                correction = self._optical_correction(letter, next_letter)
+                distance = next_letter.left - letter.right + correction
                 if distance > 5:
-                    yield Space(self.image.space(letter.right, self.top, distance, self.baseline - self.top))
+                    yield Space(self.image.space(letter.right, self.top, distance, self.height), self.baseline - self.top)
 
     def _extract_blob(self, blob_slice, label, labels):
         image = self.image[blob_slice]
@@ -150,5 +167,4 @@ class Letter(PageObject):
 
 
 class Space(Letter):
-    def __init__(self, image):
-        super().__init__(image, elevation=0)
+    pass