diff --git a/kerchunk/fits.py b/kerchunk/fits.py
index 18729a9b..4e2d53de 100644
--- a/kerchunk/fits.py
+++ b/kerchunk/fits.py
@@ -28,8 +28,8 @@
     16: ">i2",
     32: ">i4",
     64: ">i8",
-    -32: "float32",
-    -64: "float64",
+    -32: ">f4",
+    -64: ">f8",
 }  # always bigendian
 
 
diff --git a/tests/test_fits.py b/tests/test_fits.py
index 14ea6fc0..2ec19216 100644
--- a/tests/test_fits.py
+++ b/tests/test_fits.py
@@ -13,6 +13,20 @@
 var = os.path.join(testdir, "variable_length_table.fits")
 
 
+def test_image():
+    # this one directly hits a remote server - should cache?
+    url = "https://fits.gsfc.nasa.gov/samples/WFPC2ASSNu5780205bx.fits"
+    out = kerchunk.fits.process_file(url)
+    m = fsspec.get_mapper("reference://", fo=out, remote_protocol="https")
+    g = zarr.open(m)
+    arr = g["PRIMARY"][:]
+    with fsspec.open(
+        "https://fits.gsfc.nasa.gov/samples/WFPC2ASSNu5780205bx.fits"
+    ) as f:
+        hdu = fits.getdata(f)
+        assert (hdu == arr).all()
+
+
 def test_ascii_table():
     # this one directly hits a remote server - should cache?
     url = "https://fits.gsfc.nasa.gov/samples/WFPC2u5780205r_c0fx.fits"
diff --git a/tests/test_grib.py b/tests/test_grib.py
index 1cee1e7f..ac297b01 100644
--- a/tests/test_grib.py
+++ b/tests/test_grib.py
@@ -292,7 +292,7 @@ def test_parse_grib_idx_invalid_url():
 
 
 def test_parse_grib_idx_no_file():
-    with pytest.raises(FileNotFoundError):
+    with pytest.raises((FileNotFoundError, PermissionError)):
         # the url is spelled wrong
         parse_grib_idx(
             "s3://noaahrrr-bdp-pds/hrrr.20220804/conus/hrrr.t01z.wrfsfcf01.grib2",