diff --git a/testmaps/q2_light_group.map b/testmaps/q2_light_group.map
index 195c56c5..ed5101c7 100644
--- a/testmaps/q2_light_group.map
+++ b/testmaps/q2_light_group.map
@@ -79,11 +79,12 @@
 }
 // entity 2
 {
-"classname" "light"
+"classname" "light_mine2"
 "origin" "680 1176 1000"
 "light" "300"
 "_light_channel_mask" "2"
 "_shadow_channel_mask" "2"
+"wait" ".5"
 }
 // entity 3
 {
@@ -91,11 +92,29 @@
 "_object_channel_mask" "2"
 // brush 0
 {
+( 656 1280 944 ) ( 656 1281 944 ) ( 656 1280 945 ) e1u1/twall2_1 -32 0 0 1 1
+( 656 1280 944 ) ( 656 1280 945 ) ( 657 1280 944 ) e1u1/twall2_1 0 0 0 1 1
+( 656 1280 976 ) ( 657 1280 976 ) ( 656 1281 976 ) e1u1/twall2_1 0 32 0 1 1
+( 656 1280 1024 ) ( 656 1281 1024 ) ( 657 1280 1024 ) e1u1/twall2_1 0 32 0 1 1
+( 704 1296 960 ) ( 705 1296 960 ) ( 704 1296 961 ) e1u1/twall2_1 0 0 0 1 1
+( 704 1312 960 ) ( 704 1312 961 ) ( 704 1313 960 ) e1u1/twall2_1 -32 0 0 1 1
+}
+// brush 1
+{
 ( 656 1248 944 ) ( 656 1249 944 ) ( 656 1248 945 ) e1u1/twall2_1 0 0 0 1 1
 ( 656 1248 944 ) ( 656 1248 945 ) ( 657 1248 944 ) e1u1/twall2_1 0 0 0 1 1
-( 656 1248 944 ) ( 657 1248 944 ) ( 656 1249 944 ) e1u1/twall2_1 0 0 0 1 1
+( 656 1248 960 ) ( 657 1248 960 ) ( 656 1249 960 ) e1u1/twall2_1 0 0 0 1 1
 ( 704 1280 1040 ) ( 704 1281 1040 ) ( 705 1280 1040 ) e1u1/twall2_1 0 0 0 1 1
-( 704 1280 960 ) ( 705 1280 960 ) ( 704 1280 961 ) e1u1/twall2_1 0 0 0 1 1
+( 704 1264 960 ) ( 705 1264 960 ) ( 704 1264 961 ) e1u1/twall2_1 0 0 0 1 1
 ( 704 1280 960 ) ( 704 1280 961 ) ( 704 1281 960 ) e1u1/twall2_1 0 0 0 1 1
 }
+// brush 2
+{
+( 656 1280 944 ) ( 656 1281 944 ) ( 656 1280 945 ) e1u1/twall2_1 -32 0 0 1 1
+( 656 1280 944 ) ( 656 1280 945 ) ( 657 1280 944 ) e1u1/twall2_1 0 0 0 1 1
+( 656 1280 1072 ) ( 657 1280 1072 ) ( 656 1281 1072 ) e1u1/twall2_1 0 32 0 1 1
+( 704 1312 1104 ) ( 704 1313 1104 ) ( 705 1312 1104 ) e1u1/twall2_1 0 32 0 1 1
+( 704 1296 960 ) ( 705 1296 960 ) ( 704 1296 961 ) e1u1/twall2_1 0 0 0 1 1
+( 704 1312 960 ) ( 704 1312 961 ) ( 704 1313 960 ) e1u1/twall2_1 -32 0 0 1 1
+}
 }
diff --git a/tests/test_ltface.cc b/tests/test_ltface.cc
index 2fe6e00b..152c7f8b 100644
--- a/tests/test_ltface.cc
+++ b/tests/test_ltface.cc
@@ -294,11 +294,12 @@ TEST_CASE("negative lights work") {
     }
 }
 
-TEST_CASE("_light_group") {
+TEST_CASE("light channel mask (_object_channel_mask, _light_channel_mask, _shadow_channel_mask)") {
     auto [bsp, bspx] = LoadTestmap("q2_light_group.map", {});
+    REQUIRE(2 == bsp.dmodels.size());
 
     {
-        INFO("world doesn't receive light from the light ent with '_light_group' 'pillar'");
+        INFO("world doesn't receive light from the light ent with _light_channel_mask 2");
 
         auto *face_under_light = BSP_FindFaceAtPoint(&bsp, &bsp.dmodels[0], {680, 1224, 944});
         REQUIRE(face_under_light);
@@ -309,7 +310,7 @@ TEST_CASE("_light_group") {
     }
 
     {
-        INFO("pillar with matching _light_group is receiving light");
+        INFO("pillar with _object_channel_mask 2 is receiving light");
 
         auto *face_on_pillar = BSP_FindFaceAtPoint(&bsp, &bsp.dmodels[1], {680, 1248, 1000});
         REQUIRE(face_on_pillar);
@@ -318,4 +319,26 @@ TEST_CASE("_light_group") {
             CHECK(sample[0] > 100);
         });
     }
+
+    {
+        INFO("_object_channel_mask 2 implicitly makes bmodels cast shadow in channel 2");
+
+        auto *occluded_face = BSP_FindFaceAtPoint(&bsp, &bsp.dmodels[1], {680, 1280, 1000});
+        REQUIRE(occluded_face);
+
+        CheckFaceLuxels(bsp, *occluded_face, [](qvec3b sample) {
+            CHECK(sample[0] == 0);
+        });
+    }
+
+    {
+        INFO("ensure AABB culling isn't breaking light channels");
+
+        auto *unoccluded_face = BSP_FindFaceAtPoint(&bsp, &bsp.dmodels[1], {680, 1280, 1088});
+        REQUIRE(unoccluded_face);
+
+        CheckFaceLuxels(bsp, *unoccluded_face, [](qvec3b sample) {
+            CHECK(sample[0] > 100);
+        });
+    }
 }