Metahuman eye translucency causing black blobs

I am trying to use translucency for some glass in my scene and it’s causing the eyes to have black blobs in them, I’ve tracked it down to the M_Eye_Occlusion material but I have no idea how to fix the issue, if I drop another transparent material in the the M_Eye_Occlusion slot then I can fix this but lose some of the eye detail around the edges. Does anyone know how to fix this? Thanks :v:


Same here. When I activate Ray tracing translucency (since I need it in scene), there are dark blobs in eyes and eyelashes (card one that I don’t need at all).
Seems like it was a common issue with eye shader, written that it was fixed in 4.26.2 exacly

How do we correct this issue then?

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Raytracing translucency seemed to have some bugginess on the Car Configurator model as well, albeit different (didn’t look there was any material at all)

The issue with Metahumans with RT translucency is coming from eyeocclusion mesh and eyelashes mesh. Can anyone help please how we need to modify the eyeocclusion material in order to work? And how to remove eyelashes cards? I already assigned invis material to eyelashes but the artifacts are still there. I’m interested only in LOD0, which should have groom eyelashes

Turn translucency refraction off in post process under ray tracing translucency to stop eye lash shadows. As for the black in the eyes I’m still struggling with that. You might also need to turn on translucency. Let me know if that fixed your shadow issue?

Yeah, but I exactly need the RT refraction in my scene. Can’t I just really hide these card eyelashes? I don’t need them, since I’m using the groom eyelashes. But assigning invisible material doesn’t fix the issue

The black blobs issue seems to appear as soon as raytracing is enabled in the project settings. The eyes go black if there isn’t any direct light hitting on it and also if I go far the eyes transition to what it’s supposed to look like in the first place, but when I move closer it slowly fades to black , I see this is an issue with the eye occlusion shader. This issue happens mainly when using an HDri backdrop or a skylight. Is someone else facing the same issue?

Test_2 Test_3

I got the same probleme. I don’t think it come from the eye occlusion mesh but rather from the eye shader. I have remove the eye occlusion shader and the eye are still black with raytracing enabled.
It look like the eye is not working with the hdri backdrop when raytracing is enabled.

Go to blueprint - on the left hand side under components double click on “face” - On the right hand side in the materials tab double click on “Element 5” - On the right hand side under General double click “Parent” - On the left hand side under Material change the blend mode to “Additive”. Hope this helps :v:


this worked thanks!

thanks a ton for this fix - was driving me nuts.

Thanks alot !

For me the issue was in the HDRI Backdrop. Click on the HDRIBackdrop blueprint in the world outliner, select the Skylight, scroll down under “Light” there is a Transmission checkbox. Check this on and it should fix the eyes. - Hopefully this helps someone.


thank you…thank a lot

I have an issue related to Ray Traced Translucency as well. When turned off in post process, the issue is gone. Does anyone has a solution for this? I need ray traced translucency in my scene.

To get rid of the hair (eyelash) cards, you should be able to go into the groom asset editor and, underneath the LOD window, set the screen size of all LOD’s other than 0 to 0.0 [I tend to use 0.05].
The same applies if your groom disappears too close to camera, the smaller the number, the further the camera has to be before it moves to the next LOD.

Brilliant. Thank you.

Obrigado por essa dica! Tive esse problema na versão 5.3 e passei a tarde em busca de uma solução. Thank you!

It’s not the solution, if you do that the eye occlusion doesn’t work anymore

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