diff --git a/aict_tools/__init__.py b/aict_tools/__init__.py
index 66d9d1e..cc37364 100644
--- a/aict_tools/__init__.py
+++ b/aict_tools/__init__.py
@@ -1 +1 @@
-__version__ = '0.22.1'
+__version__ = '0.22.2'
diff --git a/aict_tools/cta_helpers.py b/aict_tools/cta_helpers.py
index 3133951..082609c 100644
--- a/aict_tools/cta_helpers.py
+++ b/aict_tools/cta_helpers.py
@@ -13,12 +13,12 @@ def horizontal_to_camera_cta_simtel(zd, az, zd_pointing, az_pointing, focal_leng
         altaz = AltAz()
         source_altaz = SkyCoord(
             az=u.Quantity(az, u.deg, copy=False),
-            alt=u.Quantity(zd, u.deg, copy=False),
+            alt=u.Quantity(90 - zd, u.deg, copy=False),
             frame=altaz,
         )
 
         tel_pointing = SkyCoord(
-            alt=u.Quantity(zd_pointing, u.deg, copy=False),
+            alt=u.Quantity(90 - zd_pointing, u.deg, copy=False),
             az=u.Quantity(az_pointing, u.deg, copy=False),
             frame=altaz,
         )
@@ -26,6 +26,6 @@ def horizontal_to_camera_cta_simtel(zd, az, zd_pointing, az_pointing, focal_leng
             focal_length=u.Quantity(focal_length, u.m, copy=False),
             telescope_pointing=tel_pointing,
         )
- 
+
         cam_coords = source_altaz.transform_to(camera_frame)
         return cam_coords.x.to_value(u.m), cam_coords.y.to_value(u.m)
diff --git a/tests/cta_coord_test.hdf b/tests/cta_coord_test.hdf
index d898b22..d4bd2d0 100644
Binary files a/tests/cta_coord_test.hdf and b/tests/cta_coord_test.hdf differ
diff --git a/tests/test_cta_coords.py b/tests/test_cta_coords.py
index 21b9b25..13e43a1 100644
--- a/tests/test_cta_coords.py
+++ b/tests/test_cta_coords.py
@@ -9,11 +9,11 @@ def test_horizontal_to_camera():
     expected_x = df.x
     expected_y = df.y
     transformed_x, transformed_y = horizontal_to_camera_cta_simtel(
-            df.alt,
-            df.az,
-            df.alt_pointing,
-            df.az_pointing,
-            df.focal_length
+            zd=df.zd,
+            az=df.az,
+            zd_pointing=df.zd_pointing,
+            az_pointing=df.az_pointing,
+            focal_length=df.focal_length,
     )
     assert_allclose(expected_x, transformed_x)
     assert_allclose(expected_y, transformed_y)