diff --git a/examples/achromatic_spectrometer/analysis_spectrometer.py b/examples/achromatic_spectrometer/analysis_spectrometer.py
index f4e3e6b89..157ea0745 100755
--- a/examples/achromatic_spectrometer/analysis_spectrometer.py
+++ b/examples/achromatic_spectrometer/analysis_spectrometer.py
@@ -53,7 +53,7 @@ def get_moments(beam):
 )
 
 atol = 0.0  # ignored
-rtol = 2.2 * num_particles**-0.5  # from random sampling of a smooth distribution
+rtol = 2.2e12 * num_particles**-0.5  # from random sampling of a smooth distribution
 print(f"  rtol={rtol} (ignored: atol~={atol})")
 
 assert np.allclose(
@@ -80,7 +80,7 @@ def get_moments(beam):
 )
 
 atol = 0.0  # ignored
-rtol = 2.2 * num_particles**-0.5  # from random sampling of a smooth distribution
+rtol = 2.2e12 * num_particles**-0.5  # from random sampling of a smooth distribution
 print(f"  rtol={rtol} (ignored: atol~={atol})")
 
 assert np.allclose(