# Ray Traced Shadows Subsurface Scattering transmission broken 5.1 **URL:** \ **Category:** Feedback & Requests\ **Tags:** unreal-engine, Lighting\ **Created:** [December 25, 2022, 5:10pm UTC](https://forums.unrealengine.com/t/ray-traced-shadows-subsurface-scattering-transmission-broken-5-1/735714 "2022-12-25T17:10:21Z")\ **Posts on this page:** 12\ **Page:** 1
**Author:** ![ItsSharp](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/itssharp/32/1015721_2.png) [@ItsSharp](https://forums.unrealengine.com/u/ItsSharp)\ **Post date:** [December 25, 2022, 5:10pm UTC](https://forums.unrealengine.com/t/ray-traced-shadows-subsurface-scattering-transmission-broken-5-1/735714/1 "2022-12-25T17:10:22Z")
Seems like Subsurface shading model is bugged in 5.1 and has a weird shadow effect. Was wondering if anyone else had this issue and if there’s a cvar to fix it. ![image](https://d3kjluh73b9h9o.cloudfront.net/original/4X/3/5/e/35e48cf1a6b6c9012933a265e14499f0ea1e58e4.jpeg) This picture is 5.0 using a fully transmissive material ![image](https://d3kjluh73b9h9o.cloudfront.net/original/4X/e/e/8/ee83e651d6ee7ad3949be8a0c95fd508ba5dc641.jpeg) This is the same material in the same scene in 5.1 ![image](https://d3kjluh73b9h9o.cloudfront.net/original/4X/3/9/2/392c4cfb286f7c7bc45844083b4323e240225020.jpeg) SSS shows up fine in path tracing ![image](https://d3kjluh73b9h9o.cloudfront.net/original/4X/a/2/3/a230375685dd65ca9c88472144a2a37201ed8cb8.jpeg) Again broken with just a plain untouched shading model in RT shadows. ---
**Author:** ![JosephNickson1](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@JosephNickson1](https://forums.unrealengine.com/u/JosephNickson1)\ **Post date:** [March 13, 2023, 9:45am UTC](https://forums.unrealengine.com/t/ray-traced-shadows-subsurface-scattering-transmission-broken-5-1/735714/2 "2023-03-13T09:45:51Z")
Hey, Was about to make a thread flagging the same issue. ![image](https://d3kjluh73b9h9o.cloudfront.net/original/4X/6/4/5/645e5b8e779ac38477329dc37aa1345c3989206c.jpeg) Everything working as intended on 5.0.3 ![image2](https://d3kjluh73b9h9o.cloudfront.net/original/4X/8/d/6/8d6a4389f7f124e049eadc59b692ee21d61daa31.jpeg) Then entirely broken ray traced shadows in 5.1, 5.11 and also 5.2 which I just compiled from github. Seems there’s no light contribution past direct lit areas, making SSS a bit pointless as it stands. Having to stick with 5.0.3, but really needed 5.1 for a couple other bug fixes. ---
**Author:** ![ItsSharp](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/itssharp/32/1015721_2.png) [@ItsSharp](https://forums.unrealengine.com/u/ItsSharp)\ **Post date:** [March 16, 2023, 11:43pm UTC](https://forums.unrealengine.com/t/ray-traced-shadows-subsurface-scattering-transmission-broken-5-1/735714/3 "2023-03-16T23:43:47Z")
I made a bug report when I originally posted here. Sadly doesn’t seem like it got noticed or anything. I hope it gets fixed or a full 5.2 or 5.21 release because besides using 5.0.3, I can’t find a ray tracing workaround, but you can use lumen shadows which work you just lose all your nice ray tracing. ---
**Author:** ![JosephNickson1](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@JosephNickson1](https://forums.unrealengine.com/u/JosephNickson1)\ **Post date:** [March 20, 2023, 12:12am UTC](https://forums.unrealengine.com/t/ray-traced-shadows-subsurface-scattering-transmission-broken-5-1/735714/4 "2023-03-20T00:12:13Z")
Glad you made a report for it @ItsSharp - Do you have a link to the report made? Seems such a shame these current builds are unusable for me due to this one odd slip up. ---
**Author:** ![JosephNickson1](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@JosephNickson1](https://forums.unrealengine.com/u/JosephNickson1)\ **Post date:** [March 20, 2023, 10:40am UTC](https://forums.unrealengine.com/t/ray-traced-shadows-subsurface-scattering-transmission-broken-5-1/735714/5 "2023-03-20T10:40:00Z")
Have just built latest 5.3 build off Github, still experiencing the same issue - Just a heads up. ---
**Author:** ![ItsSharp](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/itssharp/32/1015721_2.png) [@ItsSharp](https://forums.unrealengine.com/u/ItsSharp)\ **Post date:** [March 22, 2023, 3:06am UTC](https://forums.unrealengine.com/t/ray-traced-shadows-subsurface-scattering-transmission-broken-5-1/735714/6 "2023-03-22T03:06:22Z")
They never made the report public. I have the case number Case # 00512976, but I never saw a published version on the issues page which sucks. ---
**Author:** ![JosephNickson1](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@JosephNickson1](https://forums.unrealengine.com/u/JosephNickson1)\ **Post date:** [March 22, 2023, 6:18pm UTC](https://forums.unrealengine.com/t/ray-traced-shadows-subsurface-scattering-transmission-broken-5-1/735714/7 "2023-03-22T18:18:23Z")
Tried building latest 5.3, but still encountering the same issue, seems its not been resolved/noticed behind the scenes. ---
**Author:** ![ItsSharp](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/itssharp/32/1015721_2.png) [@ItsSharp](https://forums.unrealengine.com/u/ItsSharp)\ **Post date:** [March 24, 2023, 3:24pm UTC](https://forums.unrealengine.com/t/ray-traced-shadows-subsurface-scattering-transmission-broken-5-1/735714/8 "2023-03-24T15:24:43Z")
Dang that sucks D: ---
**Author:** ![JosephNickson1](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@JosephNickson1](https://forums.unrealengine.com/u/JosephNickson1)\ **Post date:** [August 4, 2023, 10:03am UTC](https://forums.unrealengine.com/t/ray-traced-shadows-subsurface-scattering-transmission-broken-5-1/735714/9 "2023-08-04T10:03:35Z")
Any clue if this has been resolved yet? 😕 ---
**Author:** ![ItsSharp](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/itssharp/32/1015721_2.png) [@ItsSharp](https://forums.unrealengine.com/u/ItsSharp)\ **Post date:** [August 8, 2023, 2:57am UTC](https://forums.unrealengine.com/t/ray-traced-shadows-subsurface-scattering-transmission-broken-5-1/735714/10 "2023-08-08T02:57:43Z")
Afaik nope ---
**Author:** ![mtloper](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@mtloper](https://forums.unrealengine.com/u/mtloper)\ **Post date:** [January 9, 2024, 7:56pm UTC](https://forums.unrealengine.com/t/ray-traced-shadows-subsurface-scattering-transmission-broken-5-1/735714/11 "2024-01-09T19:56:28Z")
![Subsurface01](https://d3kjluh73b9h9o.cloudfront.net/original/4X/c/2/8/c28802f94ba4a726ee27d46b4565052c66881819.jpeg) ![Subsurface02](https://d3kjluh73b9h9o.cloudfront.net/original/4X/0/a/0/0a01e2b3c18813ad8f364733f86f552569dda7c1.jpeg) I just place Metahuman 5.3 in Metahumanlighting UE 5.3.2 Project. Subsurface working in the original Level MHC\_LightingPreset\_Portrait\_RT with Spotlight. But when I add new spotlight, It no work !!! All settings are same. The only way to work is if I copy spotlight already include in this level. ---
**Author:** ![mtloper](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@mtloper](https://forums.unrealengine.com/u/mtloper)\ **Post date:** [January 9, 2024, 8:30pm UTC](https://forums.unrealengine.com/t/ray-traced-shadows-subsurface-scattering-transmission-broken-5-1/735714/12 "2024-01-09T20:30:23Z")
![Subsurface025](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/285e323c8ba466246e2317d9f4635c0554854318.jpeg) ![Subsurface03](https://d3kjluh73b9h9o.cloudfront.net/original/4X/6/0/9/609bfd7b9bf818f6711ad1738b356ad2a91ae655.jpeg) mmmm… OK It was a missing setting need to check “Transmission” in spotlight This setting is disable if not movable Hope it help