Tuning constants from drive practice

Change-Id: I8a820317b693358326bb91a9df3051f481bc68b4
diff --git a/y2019/constants.cc b/y2019/constants.cc
index 5f0469e..477209e 100644
--- a/y2019/constants.cc
+++ b/y2019/constants.cc
@@ -145,7 +145,7 @@
   r->camera_noise_parameters = {.max_viewable_distance = 10.0,
                                 .heading_noise = 0.1,
                                 .nominal_distance_noise = 0.15,
-                                .nominal_skew_noise = 0.45,
+                                .nominal_skew_noise = 0.75,
                                 .nominal_height_noise = 0.01};
 
   // Deliberately make FOV a bit large so that we are overly conservative in