diff --git a/docs/issues.txt b/docs/issues.txt
index 379d7e55..73d771dd 100644
--- a/docs/issues.txt
+++ b/docs/issues.txt
@@ -9,9 +9,6 @@ ISSUES: Bugs, Cleanup and Refinements
  #    #  #       #    #     #    #       #       #   #   #    #
   ####   #        ####      #    ######  ######  #    #   ####
 
-- Active lenses facing each other go apeshit.
-	- They also totally bog the game down with lighting recalcs.
-
 - Optics should be blockable by things in item form.
 	- If sunlight_propagates on the node, and it's groups.visinv,
 	  then also check sunlight_propagates of the item def if the
diff --git a/mods/nc_optics/lens.lua b/mods/nc_optics/lens.lua
index 47debbbe..92f6512f 100644
--- a/mods/nc_optics/lens.lua
+++ b/mods/nc_optics/lens.lua
@@ -8,16 +8,21 @@ local modname = minetest.get_current_modname()
 local function lens_check(pos, node, check)
 	local face = nodecore.facedirs[node.param2]
 
-	if check(face.k) then
+	local backfed = check(face.k)
+	if backfed and node.name == modname .. ":lens" then
 		return modname .. ":lens_glow"
 	end
 
 	local fore = vector.add(pos, face.f)
-	local ll = minetest.get_node_light(fore)
-	if not ll then return end
-	local lt = 15
-	if node and node.name == modname .. ":lens_on" then lt = 14 end
-	local on = ll >= lt and face.f.y == 1
+	local on
+	if face.f.y == 1 then
+		local ll = minetest.get_node_light(fore)
+		if ll then
+			local lt = 15
+			if node and node.name == modname .. ":lens_on" then lt = 14 end
+			on = ll >= lt and face.f.y == 1
+		end
+	end
 	if not on then
 		local nnode = minetest.get_node(fore)
 		local def = minetest.registered_items[nnode.name] or {}
@@ -26,6 +31,11 @@ local function lens_check(pos, node, check)
 	if on then
 		return modname .. ":lens_on", {face.k}
 	end
+
+	if backfed then
+		return modname .. ":lens_glow"
+	end
+
 	return modname .. ":lens"
 end