diff --git a/tests/ImageSharp.Tests/Processing/Transforms/TransformTests.cs b/tests/ImageSharp.Tests/Processing/Transforms/AffineTransformTests.cs
similarity index 97%
rename from tests/ImageSharp.Tests/Processing/Transforms/TransformTests.cs
rename to tests/ImageSharp.Tests/Processing/Transforms/AffineTransformTests.cs
index 574a5c3bab..f6ef365e54 100644
--- a/tests/ImageSharp.Tests/Processing/Transforms/TransformTests.cs
+++ b/tests/ImageSharp.Tests/Processing/Transforms/AffineTransformTests.cs
@@ -129,7 +129,10 @@ namespace SixLabors.ImageSharp.Tests.Processing.Transforms
                 Matrix3x2 m = this.MakeManuallyCenteredMatrix(angleDeg, s, image);
 
                 image.Mutate(i => i.Transform(m, KnownResamplers.Bicubic));
-                image.DebugSave(provider, $"R({angleDeg})_S({s})");
+
+                string testOutputDetails = $"R({angleDeg})_S({s})";
+                image.DebugSave(provider, testOutputDetails);
+                image.CompareToReferenceOutput(provider, testOutputDetails);
             }
         }
 
diff --git a/tests/Images/External b/tests/Images/External
index 0141b2af86..9d4070dab9 160000
--- a/tests/Images/External
+++ b/tests/Images/External
@@ -1 +1 @@
-Subproject commit 0141b2af864fa3eaa63b09127dc99fb09374f235
+Subproject commit 9d4070dab9e4aefa70dcd41ef98176a5d54e644f