Document pixel range (#3826)

Document pixel range
python-pillow · May 4, 2019 · d7bf918 · d7bf918
2 parents c15dc4d + 1d67bf0
commit d7bf918
Showing 1 changed file with 4 additions and 2 deletions.
diff --git a/docs/handbook/concepts.rst b/docs/handbook/concepts.rst
@@ -24,8 +24,10 @@ To get the number and names of bands in an image, use the
 Modes
 -----
 
-The ``mode`` of an image defines the type and depth of a pixel in the
-image. The current release supports the following standard modes:
+The ``mode`` of an image defines the type and depth of a pixel in the image.
+Each pixel uses the full range of the bit depth. So a 1-bit pixel has a range
+of 0-1, an 8-bit pixel has a range of 0-255 and so on. The current release
+supports the following standard modes:
 
     * ``1`` (1-bit pixels, black and white, stored with one pixel per byte)
     * ``L`` (8-bit pixels, black and white)