Martin is spot on. IR reflects better than you think. Want to see how much? Turn of the lights in your test room and using a video camera to view the area..., fire your tanks IR. The IR "Splash" is everywhere. FYI....some cell phone cameras will not see your IR beam. Any digital camera screen will see your IR however. Impact emitters can been "glowing" with the naked eye if you are close. Outside in bright sunlight IR range is reduced about 25%. Overcast skies are best.