diff --git a/intern/cycles/scene/shader.cpp b/intern/cycles/scene/shader.cpp
index 3455a733f16..94119ed634a 100644
--- a/intern/cycles/scene/shader.cpp
+++ b/intern/cycles/scene/shader.cpp
@@ -672,10 +672,8 @@ void ShaderManager::add_default(Scene *scene)
   {
     unique_ptr<ShaderGraph> graph = make_unique<ShaderGraph>();
 
-    DiffuseBsdfNode *diffuse = graph->create_node<DiffuseBsdfNode>();
-    diffuse->set_color(make_float3(0.8f, 0.8f, 0.8f));
-
-    graph->connect(diffuse->output("BSDF"), graph->output()->input("Surface"));
+    PrincipledBsdfNode *bsdf = graph->create_node<PrincipledBsdfNode>();
+    graph->connect(bsdf->output("BSDF"), graph->output()->input("Surface"));
 
     Shader *shader = scene->create_node<Shader>();
     shader->name = "default_surface";
diff --git a/intern/cycles/scene/shader_nodes.cpp b/intern/cycles/scene/shader_nodes.cpp
index d0c6365bddb..64bd67ba48d 100644
--- a/intern/cycles/scene/shader_nodes.cpp
+++ b/intern/cycles/scene/shader_nodes.cpp
@@ -2550,7 +2550,7 @@ NODE_DEFINE(PrincipledBsdfNode)
   SOCKET_IN_FLOAT(subsurface_ior, "Subsurface IOR", 1.4f);
   SOCKET_IN_FLOAT(subsurface_anisotropy, "Subsurface Anisotropy", 0.0f);
 
-  SOCKET_IN_FLOAT(specular_ior_level, "Specular IOR Level", 0.0f);
+  SOCKET_IN_FLOAT(specular_ior_level, "Specular IOR Level", 0.5f);
   SOCKET_IN_COLOR(specular_tint, "Specular Tint", one_float3());
   SOCKET_IN_FLOAT(anisotropic, "Anisotropic", 0.0f);
   SOCKET_IN_FLOAT(anisotropic_rotation, "Anisotropic Rotation", 0.0f);
diff --git a/tests/files/render/integrator/cycles_renders/light_path_is_shadow_ray.png b/tests/files/render/integrator/cycles_renders/light_path_is_shadow_ray.png
index 3b56a323e11..0da60741dd5 100644
--- a/tests/files/render/integrator/cycles_renders/light_path_is_shadow_ray.png
+++ b/tests/files/render/integrator/cycles_renders/light_path_is_shadow_ray.png
@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:5e7898024b57c6ce4ab4dd4da12de97cdda2e8ca2ac72d2e855a3321a5badd07
-size 42177
+oid sha256:706be8f834b855b1aff09df901577746df20730d8e8b73b1ebb6253f1b59d777
+size 42089
diff --git a/tests/files/render/light/cycles_renders/light_tree_multi_distant.png b/tests/files/render/light/cycles_renders/light_tree_multi_distant.png
index ccc5eac3185..20ecc89aab8 100644
--- a/tests/files/render/light/cycles_renders/light_tree_multi_distant.png
+++ b/tests/files/render/light/cycles_renders/light_tree_multi_distant.png
@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:15d5c7067906982907f89f4c4d76217c50ac4bdf27d02fdf969d0e764fddc67d
-size 21875
+oid sha256:aec0a506be19e496a888722ee9cc1abce7e5171f9a72462aaed21b3a1c7e6e29
+size 19943
diff --git a/tests/files/render/light_linking/cycles_renders/link_link_share_bit_trail.png b/tests/files/render/light_linking/cycles_renders/link_link_share_bit_trail.png
index 7430dac7cc6..2ae5bec01f7 100644
--- a/tests/files/render/light_linking/cycles_renders/link_link_share_bit_trail.png
+++ b/tests/files/render/light_linking/cycles_renders/link_link_share_bit_trail.png
@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:49a90265bd40ecdbbd00beddec9af9c104e94d5220669fdc996409140f9084f2
-size 19381
+oid sha256:63c976f6b85fb63a8ec34a89dc950cabfee0509511b5845ebd0612d728494c8e
+size 19362
diff --git a/tests/files/render/osl/cycles_renders/osl_burley_diffuse.png b/tests/files/render/osl/cycles_renders/osl_burley_diffuse.png
index 3b7f81dc2cc..4762ac9845a 100644
--- a/tests/files/render/osl/cycles_renders/osl_burley_diffuse.png
+++ b/tests/files/render/osl/cycles_renders/osl_burley_diffuse.png
@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:54da670ea1c94ac2c934e1dceae59836aba3133b40fa1a48096ecf9001f3b86c
-size 38519
+oid sha256:730d7797aa4072c0f89c4aa02a71c23763dbc39698de076887a172031683d441
+size 38385
diff --git a/tests/files/render/osl/cycles_renders/osl_ramp_closures.png b/tests/files/render/osl/cycles_renders/osl_ramp_closures.png
index b83a2a1d501..7114738a9c1 100644
--- a/tests/files/render/osl/cycles_renders/osl_ramp_closures.png
+++ b/tests/files/render/osl/cycles_renders/osl_ramp_closures.png
@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:a7c1f54de468eb589b91ea2c700e35c053e6ef12801a58895680a7f43638152b
-size 36161
+oid sha256:83d45667cf81e0369c04422614ea346196048aecda72426286843b2db070be20
+size 36278
diff --git a/tests/files/render/pointcloud/cycles_renders/points_emission.png b/tests/files/render/pointcloud/cycles_renders/points_emission.png
index 999f75315a3..b2678e4b76a 100644
--- a/tests/files/render/pointcloud/cycles_renders/points_emission.png
+++ b/tests/files/render/pointcloud/cycles_renders/points_emission.png
@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:478f593f86613fb109ff40fbae73b4e03097679b24db4180846e2f2244caf0b7
-size 34231
+oid sha256:5c40ad0fbdc54e0ba2c4ec6a444cdaac411ffda24635d8da961eedf305fadbc2
+size 34910
diff --git a/tests/files/render/reports/cycles_renders/sobol_uniform_41143.png b/tests/files/render/reports/cycles_renders/sobol_uniform_41143.png
index 6e9ff5338dd..bfac9840404 100644
--- a/tests/files/render/reports/cycles_renders/sobol_uniform_41143.png
+++ b/tests/files/render/reports/cycles_renders/sobol_uniform_41143.png
@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:4d52d3b6146bb0c93c0cdc1efbbb30659b351b3214c2e06946fef92fc5a9c907
-size 14990
+oid sha256:ba0de19b0eab53725dfb45b24e8344e14fd171330ccc7f23f50e94f15f8a7b18
+size 15413
diff --git a/tests/files/render/reports/cycles_renders/transparent_curves_50533.png b/tests/files/render/reports/cycles_renders/transparent_curves_50533.png
index 6d01afd01b5..87e16743bf5 100644
--- a/tests/files/render/reports/cycles_renders/transparent_curves_50533.png
+++ b/tests/files/render/reports/cycles_renders/transparent_curves_50533.png
@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:98b7960467f29fe773c951494331718ab7624da028cecfb5fc223be619c1bcac
-size 11486
+oid sha256:1196409803b4724d9215f4e5010236d5cd57de5cecbe776088c403a0ba64b783
+size 11783
diff --git a/tests/files/render/volume/cycles_renders/volume_zero_extinction_channel.png b/tests/files/render/volume/cycles_renders/volume_zero_extinction_channel.png
index 0fabcac4b8c..fc5fcf886a3 100644
--- a/tests/files/render/volume/cycles_renders/volume_zero_extinction_channel.png
+++ b/tests/files/render/volume/cycles_renders/volume_zero_extinction_channel.png
@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:8e631578c52b80fe98bf20f3acbd93f4916c939bd43e95821f70cae393de6a89
-size 42062
+oid sha256:548131fad78e91a46e4b92965f62ea618a538d3bd976b92802220bd7631cbb52
+size 42202