diff --git a/drizzle/tests/test_utils.py b/drizzle/tests/test_utils.py
index f4c598f..a961cb1 100644
--- a/drizzle/tests/test_utils.py
+++ b/drizzle/tests/test_utils.py
@@ -111,7 +111,26 @@ def test_estimate_pixel_scale_ratio():
     input_file = os.path.join(DATA_DIR, 'j8bt06nyq_flt.fits')
 
     with fits.open(input_file) as h:
+        hdr = h[1].header
+        assert abs(hdr['CRPIX1'] / 512 - 1) < 1e-14
+        assert abs(hdr['CRPIX2'] / 512 - 1) < 1e-14
+        assert abs(hdr['CRVAL1'] / 6.027148333333000000000 - 1) < 1e-14
+        assert abs(hdr['CRPIX2'] / 72.08351111111000000000 + 1) < 1e-14
+        assert abs(hdr['CD1_1'] / 7.360500000000000000000E-06 + 1) < 1e-14
+        assert abs(hdr['CD1_2'] / 1.845600000000000000000E-06 - 1) < 1e-14
+        assert abs(hdr['CD2_1'] / 2.868580000000000000000E-06 - 1) < 1e-14
+        assert abs(hdr['CD2_2'] / 6.649460000000000000000E-06 - 1) < 1e-14
         w = wcs.WCS(h[1].header)
+        assert np.allclose(w.wcs.crval, [6.027148333333000000000, -72.08351111111000000000], rtol=1e-14)
+        assert np.allclose(w.wcs.crpix, [512.0, 512.0], rtol=1e-14)
+        assert np.allclose(
+            w.wcs.cd,
+            [
+                [-7.360500000000000000000E-06, 1.845600000000000000000E-06],
+                [2.868580000000000000000E-06, 6.649460000000000000000E-06]
+            ],
+            rtol=1e-14
+        )
 
     pscale = estimate_pixel_scale_ratio(w, w, w.wcs.crpix, (0, 0))