Votes
0
Product:
Character Creator 4
Version:
4.4
Status:
Closed
Issue 11292
Part of the face of a model created using Headshot is discolored in Unreal Engine
Dear person in charge

Hello,
I am experiencing unnatural changes in the tint of models imported on Unreal Engine 5 and would like to seek support.

The model is created from a 3D scan image of a face using CC4 and Headshot and exported as an FBX.
When importing the FBX into UE5 using Auto Character Setup for Unreal Engine 5, I am experiencing an issue where the tint of some facial parts changes extremely unnaturally under certain lighting conditions.
Specifically, only the eyes and mouth area appear strongly reddened and look as if they have cried and swollen.
(I am attaching some screenshots).

When placed on a map of MetaHuman Lighting presets MHC_LightingPreset_Portrait_RT (I think this is one of the most standard lighting) or MHC_LightingPreset_Moonlight_RT, the effect of lighting becomes noticeable.

This problem occurs only in models created using headshot, not in other CC4 sample models.
I have followed the official tutorial here for generating models from 3D scans with Headshot.

To reproduce the problem:
- Generate the model by setting the texture of the scan data in Diffuse according to the Headshot tutorial.
- Export the generated model from CC4 to FBX format for Unreal
- Import the FBX using Auto Character Setup in Unreal Engine and place it on the lighting preset in MetaHuman Lighting

I looked at the exported FBX textures and found an image with red around the eyes, but I am not sure if this is related or not. (In UE, not only around the eyes, but also around the mouth is red).
I have also found that on UE, if I turn off the "Cast Shadow" setting for the lights hitting the face, this redness disappears for some reason.

It appears that there is an SSS related anomaly as the symptoms change with lighting intensity. Since the exported FBX does not contain a map for SSS, I suspect that this is an issue during import by Auto Setup for Unreal.

Is this problem a glitch in CC4 or Auto Character Setup? Is it possible to solve this problem by adjusting the model?

I wanted to attach the CC4 project file of the model in question, but due to its large size, I am sending it to you via a Google Drive link.
https://drive.google.com/file/d/1kWoD_vyGvMQ0gCzEIBN_0MvRtzYuP-Gu/view?usp=sharing

Character Creator 4.4.2509.1
Unreal Engine 5.2.1
OS: Windows 10
Attachment:
  •  2
  •  58
BugPipeline (Export/Import)VisualOptimize and DecimateHeadshotAuto Setup for Unreal
Submitted byk.kuramasu
1
COMMENTS (2)
k.kuramasu
Private Comment
Feedback Tracker Admin 
Hi k.kuramasu,

It should be because of the unreal settings.It's also fine in my Unreal 5.2.If you have any questions, you can contact us.

Molly
Reallusion
k.kuramasu 
Yes, we always import using HQ shaders.

After investigating for the past few days, we have discovered that this phenomenon only occurs with Unreal Engine 5.2, which is what we are using for this project, and not with Unreal Engine 5.3.
As this has turned out to be something that will be resolved in the future, you are welcome to close this issue. Thank you for your response.
Feedback Tracker Admin
Private Comment
Feedback Tracker Admin 
Hi k.kuramasu,

I can't repeat it.Can you provide your project file to help us identify the problem?Please attach the file in your next comment. If the file size is larger than 10MB, you can use cloud services such as Google Drive, Dropbox or OneDrive to make the files available to us and put the link in your comment. You can use Private Comment if you want to keep it private.

Your help is highly appreciated.

Molly
Reallusion
1