diff --git a/chain.png b/chain.png
index a5f5034..c145cce 100644
Binary files a/chain.png and b/chain.png differ
diff --git a/chain.pov b/chain.pov
index b113b94..e251fcb 100644
--- a/chain.pov
+++ b/chain.pov
@@ -12,7 +12,7 @@
     angle 30
   }
 
-  background { color Gray30 }
+  background { color rgb <.46, .09, .06> }
 
   light_source { <300, 300, -1000> White }
 
@@ -63,6 +63,6 @@
 
 //======= RENDER
   object { chain scale .45 }
-//  object { chain scale .45 translate < 10, 0, -20 > rotate y*20 }
-//  object { chain scale .45 translate < -10, 0, 20 > rotate y*35 }
+  object { chain scale .45 translate < 10, -10, -20 > rotate y*20 }
+  object { chain scale .45 translate < 10, 30, 20 > rotate y*30 }
 
diff --git a/csgdemo.png b/csgdemo.png
new file mode 100644
index 0000000..22ccd77
Binary files /dev/null and b/csgdemo.png differ
diff --git a/csgdemo.pov b/csgdemo.pov
new file mode 100644
index 0000000..7993510
--- /dev/null
+++ b/csgdemo.pov
@@ -0,0 +1,55 @@
+  #version 3.7;
+  #include "colors.inc"
+
+  global_settings {
+    assumed_gamma 1
+  }
+
+  camera {
+    right x*1280/720
+    location <0, 1, -10>
+    look_at 0
+    angle 36
+  }
+
+  light_source { <500, 500, -1000> White }
+
+  plane { y, -1.5
+    pigment { checker Green White }
+  }
+
+
+  #declare lens_hole = difference {
+    intersection {
+      sphere { <0, 0, 0>, 1
+        translate -0.5*x
+      }
+      sphere { <0, 0, 0>, 1
+        translate 0.5*x
+      }
+      rotate 90*y
+    }
+    cylinder { <0, 0, -1> <0, 0, 1>, .35
+    }
+  }
+
+
+  #declare thing = merge {
+    object { lens_hole translate <-.65, .65, 0> }
+    object { lens_hole translate <.65, .65, 0> }
+    object { lens_hole translate <-.65, -.65, 0> }
+    object { lens_hole translate <.65, -.65, 0> }
+    pigment { Red filter .4 }
+  }
+
+  #declare abox = difference {
+    box { -1, 1 pigment { Red } }
+    cylinder { -1.001*z, 1.001*z, 0.5 pigment { Green } }
+  }
+
+
+  intersection {
+    object { thing }
+    object { abox  }
+    translate <0 ,.25, 0>
+  }