diff --git a/code/game/machinery/camera/camera.dm b/code/game/machinery/camera/camera.dm
index b88acdcbc01..38bdd0e2f00 100644
--- a/code/game/machinery/camera/camera.dm
+++ b/code/game/machinery/camera/camera.dm
@@ -401,19 +401,24 @@ MAPPING_DIRECTIONAL_HELPERS(/obj/machinery/camera/xray, 0)
 		return FALSE
 	return TRUE
 
-/// Returns a list of turfs in this camera's view.
-/// This includes turfs that are "obscured by darkness" from the camera's POV.
+/// Returns an alist of turfs in this camera's view. This includes turfs that are "obscured by darkness" from the camera's POV.
+/// Format is "alist[turf] = null", if you need to check individual objects use "length(can_see & list(turf))". Only "&" and "in" work for checking contents, but "in" is much slower.
+/// Always have the return value of can_see as the left-hand operand, otherwise it uses list checks instead of alist checks and your CPU time gets thrown in a blender.
 /obj/machinery/camera/proc/can_see()
-	var/list/see = null
+	var/alist/see = alist()
 	var/turf/pos = get_turf(src)
 	var/turf/directly_above = GET_TURF_ABOVE(pos)
 	var/check_lower = pos != get_lowest_turf(pos)
 	var/check_higher = directly_above && istransparentturf(directly_above) && (pos != get_highest_turf(pos))
 
 	if(isXRay())
-		see = RANGE_TURFS(view_range, pos)
+		see += RANGE_TURFS(view_range, pos)
 	else
-		see = get_hear_turfs(view_range, pos)
+		var/lum = pos.luminosity
+		pos.luminosity = 6
+		for(var/turf/turf in view(view_range, pos))
+			see += turf
+		pos.luminosity = lum
 
 	if(check_lower || check_higher)
 		// Haha datum var access KILL ME
@@ -428,6 +433,7 @@ MAPPING_DIRECTIONAL_HELPERS(/obj/machinery/camera/xray, 0)
 				while(above && istransparentturf(above))
 					see += RANGE_TURFS(1, above)
 					above = GET_TURF_ABOVE(above)
+
 	return see
 
 /obj/machinery/camera/proc/Togglelight(on=0)
diff --git a/code/modules/mob/living/silicon/ai/freelook/chunk.dm b/code/modules/mob/living/silicon/ai/freelook/chunk.dm
index 23098ab15e9..5a9c093a31b 100644
--- a/code/modules/mob/living/silicon/ai/freelook/chunk.dm
+++ b/code/modules/mob/living/silicon/ai/freelook/chunk.dm
@@ -121,7 +121,8 @@
 			if(get_dist(point, current_camera) > CHUNK_SIZE + (CHUNK_SIZE / 2))
 				continue
 
-			for(var/turf/vis_turf as anything in turfs & current_camera.can_see())
+			// The return value of can_see being the left-hand operand here is a load-bearing performance pillar
+			for(var/turf/vis_turf as anything in current_camera.can_see() & turfs)
 				updated_visible_turfs[vis_turf] = vis_turf
 
 	///new turfs that we couldnt see last update but can now
@@ -164,7 +165,6 @@
 
 		client.images += active_static_images
 
-
 /// Create a new camera chunk, since the chunks are made as they are needed.
 /datum/camerachunk/New(x, y, lower_z)
 	x = GET_CHUNK_COORD(x)
@@ -206,7 +206,7 @@
 			if(!camera.can_use())
 				continue
 
-			for(var/turf/vis_turf as anything in turfs & camera.can_see())
+			for(var/turf/vis_turf as anything in camera.can_see() & turfs)
 				visibleTurfs[vis_turf] = vis_turf
 
 	for(var/turf/obscured_turf as anything in turfs - visibleTurfs)
diff --git a/code/modules/modular_computers/file_system/programs/secureye.dm b/code/modules/modular_computers/file_system/programs/secureye.dm
index 7a91b9f00aa..491d1402512 100644
--- a/code/modules/modular_computers/file_system/programs/secureye.dm
+++ b/code/modules/modular_computers/file_system/programs/secureye.dm
@@ -174,7 +174,7 @@
 		CRASH("[src] was able to track [target] through /datum/trackable, but was not on a visible turf to cameras.")
 	for(var/obj/machinery/camera/cameras as anything in target_camerachunk.cameras[target.z])
 		// We need to find a particular camera that can see this turf
-		if(!(target_turf in cameras.can_see()))
+		if(length(cameras.can_see() & list(target_turf)))
 			continue
 		var/new_camera = WEAKREF(cameras)
 		if(camera_ref == new_camera)