diff --git a/SDFMapCreator/SdfKernels.Kernels.cs b/SDFMapCreator/SdfKernels.Kernels.cs
index 81d663e..db33700 100644
--- a/SDFMapCreator/SdfKernels.Kernels.cs
+++ b/SDFMapCreator/SdfKernels.Kernels.cs
@@ -5,12 +5,14 @@ using ILGPU.Runtime;
 namespace SDFMapCreator;
 
 public partial class SdfKernels {
+    
+    private const float LUMA_THRESHOLD = 0.0f;
     static void SelfMaskKernel(Index2D index, ArrayView2D<Vector3, Stride2D.DenseX> input, ArrayView2D<Vector3, Stride2D.DenseX> mask) {
         var x = index.X;
         var y = index.Y;
         var value = input[x, y];
-        var lumaA = (value.X + value.Y + value.Z) / 3f;
-        var r = lumaA > 0.99f ? 1f : 0f;
+        var lumaA = value.X;
+        var r = lumaA > LUMA_THRESHOLD ? 1f : 0f;
         mask[x, y] = new(r, 0f, 0f);
     }
 
@@ -23,9 +25,9 @@ public partial class SdfKernels {
         var y = index.Y;
         var valueA = A[x, y];
         var valueB = B[x, y];
-        var lumaA = (valueA.X + valueA.Y + valueA.Z) / 3f;
-        var lumaB = (valueB.X + valueB.Y + valueB.Z) / 3f;
-        var r = lumaA > 0.99f && lumaB > 0.99f ? 1f : 0f;
+        var lumaA = valueA.X;
+        var lumaB = valueB.X;
+        var r = lumaA > LUMA_THRESHOLD || lumaB > LUMA_THRESHOLD ? 1f : 0f;
         mask[x, y] = new(r, 0f, 0f);
     }