diff --git a/test/geom/frustum.cpp b/test/geom/frustum.cpp
index 71646480..8b2cb581 100644
--- a/test/geom/frustum.cpp
+++ b/test/geom/frustum.cpp
@@ -14,7 +14,7 @@ main ()
     util::TAP::logger tap;
 
     const util::geom::frustum3f origin90 (
-        util::perspective (90.f, 1.f, {0.01f, 1.f})
+        util::perspective (util::to_radians (90.f), 1.f, {0.01f, 1.f})
     );
 
     static const struct {