UDIM question

[stephaniebellgardt]

Hey guys, another UDIM question from me. I have a high-detail creature model that I originally gave 10 UDIMs in Maya. I did all my sculpting work after that in ZBrush, and out of curiosity, I duplicated the model and reprojected my sculpt onto a single-UV version, just to see the difference. But in final render, the two looked almost identical. Wondering why this would happen, since a 10-UDIM setup should look much better than a single-tile setup?

I've attached a picture of the WIP sculpt (top one is the 1-tile version) as well as the displacements for the single-tile UV layout, versus the first tile of the 10-UDIM layout.

[damaggio]

I think I already explained to you Stephanie in your previous post, you are just reprojecting the same sculpt resolution on a bigger UV map, you need to upres your sculpt in Zbrush. It's the same problem as baking the texture maps into these new UDIMs. Also what are the resolution on these maps?

[Christoph_Schaedl]

Import the highres or a part of it to check if you need more resolution.

[stephaniebellgardt]

This is a reverse of that issue. My original model was 10 UDIMs and sculpted that way. I downsized to 1 UDIM tile for comparison and got the same result -- that's what I'm confused about. Shouldn't it look worse than the original 10-UDIM version?

[Christoph_Schaedl]

It will look the same if your model in zbrush does not have enough detail. Render the highress geo to see the max Quality.

[stephaniebellgardt]

The level of detail is fine and I’m getting good renders that match my sculpt. My only question was why the 1-UDIM version wouldn’t look much lower quality than the 10-UDIM version.

[Christoph_Schaedl · Accepted solution]

If all your poly and details do match the quality of an 4k map you wont gain anything from UDIMS.

If your model does have 200mio poly highly detailed you will get much better quality with UDIMs.

[stephaniebellgardt]

thanks for the help! So are UDIMS really only useful for, like, massive models that have insane close-up details? I read the Game of Thrones dragons had something like 160 UDIMS for season 6.

[damaggio]

Yes, when we make models in production they can have from 2 to hundreds of UDims, specialy for Imax releases ,for game work this is still very limited.It's important not to change the resolution of an asset, this can lead to a lot of additional work. A solo artist should stablish the resolution needed for the project at the very ealy stages of design.

[stephaniebellgardt]

Fortunately I’m the only one dealing with this asset until it gets further down the pipeline, and I’ve been able to adjust the UV’s accordingly. Thanks for the info!

[1410arabele]

1. Resolution of Textures: If the resolution of the textures for the single-UV tile setup is high enough, it can capture almost as much detail as the 10-UDIM setup. Ensure you're comparing textures of the same resolution.

2. Render Settings: Render settings such as anti-aliasing, sampling, and texture filtering can affect the final appearance. High-quality render settings might minimize the visual differences between the two setups.

3. Level of Detail (LOD): Depending on your renderer and settings, it might be using LOD techniques that reduce the apparent differences between the two setups, especially if the camera is not extremely close to the model.

4. Displacement Map Quality: The quality and resolution of the displacement maps can also play a significant role. If the displacement maps are detailed enough for the single-UV setup, they might look similar to the 10-UDIM setup.

5. Viewport Display vs. Render Output: Sometimes, the viewport display settings might not show the true resolution or differences between the two setups. Always compare the final rendered images.

6. Shader and Material Settings: Ensure that the shaders and materials are set up correctly to utilize the detail provided by the 10-UDIM setup. Sometimes, incorrect settings might not take full advantage of the extra detail.

Troubleshooting Steps:

1. Compare Texture Resolutions: Check the resolution of the textures used in both setups. Higher resolution textures for the single-UV setup might explain the minimal difference.
2. Render Settings: Verify that your render settings are high enough to showcase the differences in detail.
3. Zoom In: Examine the renders closely, especially in areas with fine detail, to see if there are subtle differences that might not be apparent at a distance.
4. Material Setup: Ensure that the materials and shaders are correctly configured to use the UDIM textures.

Example Render Settings Check:

• Anti-aliasing: Ensure it is set to a high level.
• Texture Filtering: Set to high-quality modes.
• Displacement Settings: Ensure that the displacement map settings are optimized for high detail.

Conclusion:

While 10-UDIMs should theoretically provide more detail, practical differences in render settings, texture resolution, and displacement map quality can result in similar visual output. Review your workflow and settings to ensure you're utilizing the full potential of the 10-UDIM setup