diff --git a/src/gray.f b/src/gray.f
index 637afd1..0b0302a 100644
--- a/src/gray.f
+++ b/src/gray.f
@@ -468,7 +468,7 @@ c     if found, use its polarization state to compute mode coupling
                 end do powloop
 c     if no ray completed a first pass in the plasma, use central ray
 c     initial polarization (possibly reflected)
-                if (qqout.le.0.0_wp_) then
+                if (qqout**2+uuout**2+vvout**2.le.0.0_wp_) then
                   call stokes(ext(1,1,0),eyt(1,1,0),qqout,uuout,vvout)
                 end if
                 powrfl=0.5_wp_*(1.0_wp_+vvout*vvin2+