diff --git a/adafruit_pypixelbuf.py b/adafruit_pypixelbuf.py
index c0d0469..3cb83e9 100644
--- a/adafruit_pypixelbuf.py
+++ b/adafruit_pypixelbuf.py
@@ -98,6 +98,9 @@ def __init__(  # pylint: disable=too-many-locals,too-many-arguments
                 byteorder_tuple[2] + 1,
                 0,
             )
+            # Initialize the buffer with the dotstar start bytes.
+            for i in range(self._offset, self._bytes + self._offset, 4):
+                self._post_brightness_buffer[i] = DOTSTAR_LED_START_FULL_BRIGHT
 
         self._brightness = 1.0
         self.brightness = brightness
@@ -252,9 +255,7 @@ def _parse_color(self, value):
                 # LED startframe is three "1" bits, followed by 5 brightness bits
                 # then 8 bits for each of R, G, and B. The order of those 3 are configurable and
                 # vary based on hardware
-                # same as math.ceil(brightness * 31) & 0b00011111
-                # Idea from https://www.codeproject.com/Tips/700780/Fast-floor-ceiling-functions
-                w = (32 - int(32 - w * 31) & 0b00011111) | DOTSTAR_LED_START
+                w = (int(w * 31) & 0b00011111) | DOTSTAR_LED_START
             elif (
                 self._has_white
                 and (isinstance(value, int) or len(value) == 3)