Noticed that when zoomed in full, tracers from ground based guns (sometimes airborne guns too but I need to test this more), disappear once you hit full zoom. Zooming out, the tracers come back once you back off about 25% from full zoom. They are visible when unzoomed, but as you get close to full zoom, they're gone. Just with the Rift, haven't tried the Vive again yet to see if the same thing happens.