diff --git a/scico/linop/xray/_xray.py b/scico/linop/xray/_xray.py
index 074ab1fc..a8ef4cf1 100644
--- a/scico/linop/xray/_xray.py
+++ b/scico/linop/xray/_xray.py
@@ -116,7 +116,9 @@ def __init__(
 
         super().__init__(
             input_shape=self.input_shape,
+            input_dtype=np.float32,
             output_shape=self.output_shape,
+            output_dtype=np.float32,
             eval_fn=self.project,
             adj_fn=self.back_project,
         )
@@ -283,7 +285,7 @@ def __init__(
         """
 
         self.input_shape: Shape = input_shape
-        self.matrices = matrices
+        self.matrices = jnp.asarray(matrices, dtype=np.float32)
         self.det_shape = det_shape
         self.output_shape = (len(matrices), *det_shape)
         super().__init__(
diff --git a/scico/test/linop/xray/test_xray.py b/scico/test/linop/xray/test_xray.py
index 960a9947..b9e12776 100644
--- a/scico/test/linop/xray/test_xray.py
+++ b/scico/test/linop/xray/test_xray.py
@@ -81,6 +81,7 @@ def test_3d_scaling():
     # default spacing
     M = XRayTransform3D.matrices_from_euler_angles(input_shape, output_shape, "X", [0.0])
     H = XRayTransform3D(input_shape, matrices=M, det_shape=output_shape)
+
     # fmt: off
     truth = jnp.array(
         [[[0.0, 0.0, 0.0, 0.0],