diff --git a/topics/imaging/tutorials/imaging-introduction/workflows/Galaxy-Workflow-GTN_Tutorial__Introduction_to_Imaging-tests.yml b/topics/imaging/tutorials/imaging-introduction/workflows/Galaxy-Workflow-GTN_Tutorial__Introduction_to_Imaging-tests.yml
index 8ca5fa3b2111ae..cbe40c697a208a 100644
--- a/topics/imaging/tutorials/imaging-introduction/workflows/Galaxy-Workflow-GTN_Tutorial__Introduction_to_Imaging-tests.yml
+++ b/topics/imaging/tutorials/imaging-introduction/workflows/Galaxy-Workflow-GTN_Tutorial__Introduction_to_Imaging-tests.yml
@@ -6,10 +6,8 @@
       filetype: tiff
   outputs:
     out_png:
-      asserts:
-        has_size:
-          value: 603419
-          delta: 100000
+      path: test-data/out.png
+      compare: image_diff
     output:
       path: test-data/output.tabular
       compare: diff
diff --git a/topics/imaging/tutorials/imaging-introduction/workflows/test-data/out.png b/topics/imaging/tutorials/imaging-introduction/workflows/test-data/out.png
new file mode 100644
index 00000000000000..51eba2dcb3139c
Binary files /dev/null and b/topics/imaging/tutorials/imaging-introduction/workflows/test-data/out.png differ