Strictly for Bump map - the Strength property, but I don't think you don't checked. Also, maybe they are made for Normal, not for Bump.
However, to me it looks like the prop is made by more meshes, and some of them (grill, wheel) are missing the diffuse map in the first place.
You could try to experiment putting the bump into the displacement with auto-assign to bump, then try to adjust roughly displacement to see if there's any changes.

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Software developer. iClone hobbyist since January 11, 2020. Best work so far: Robots among us: The Lab and The sad end of a legend
In progress: Black Mamba
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I have a model which uses a bump map to create some height detail. In Blender the bump map works as expected but when I apply it in iClone it does not seem to have any effect. I have tried using both a PNG and a BMP for the height map (since some channel, such as Opacity, use the Alpha channel when provided a PNG) but in neither case did the bump map seem to do anything.

Here is a render from Blender. Note the front grill, hub caps, door outline and door handle...



Now look at the same model in iClone. As can be seen the (same) Bump map is applied but it does not seem to have any effect. The grill, hub cap, door and handle details are all missing.


 
I noticed this happening on some of my other content but I have not yet been able to determine what is causing it. Does anyone have some suggestions that I could try to get my bump map working?

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