diff --git a/pixelocr/page.py b/pixelocr/page.py
index 94bc62d..572156c 100644
--- a/pixelocr/page.py
+++ b/pixelocr/page.py
@@ -161,7 +161,7 @@ class Line(PageObject):
         """Detect baseline height, relative to the top."""
         skip = self.height // 2
         bitmap = self.image.bitmap[skip:, :]
-        bitmap = grey_closing(bitmap, (0, 10), mode='constant')
+        bitmap = grey_closing(bitmap, (0, 4), mode='constant')
         histogram = bitmap.sum(axis=1)
         gradient = list(filters.correlate1d(histogram, [-1, 1], axis=0, mode='constant'))
         gradient[0] = histogram[0]