Thanks, I need to try that on my Tracer hair 
try to crank up subdivision modifier if you used some.
I got similar distortions once when i create a vinyl shader…
BTW Great style!
Okay,
The bump can look grainy limited with regions if the bump image doesn’t have 16-bit per color component.
Also for the bump map image I can see it’s set in “color” mode which applies unwanted gamma curve to the data. Use of “non-color” would be recommended.
If the rendering is done with Eevee then it’s unfortunate technical limitation of the current approach that the bump map output in the resulting image is rendered only in half resolution.
The proposed solution fo this case is to use normal maps. Though normal map rendering requires UV unwrapping which can lead to problems with meshes using lots of modifiers and often requires lots of additional work.
Indeed @Xard , I’ve to use the non-color parameter for bump & alpha texture!!! Thank you! But the result is the same.
I’ve streched my UV in order to have more bump details, and it seems to work better!
I have to test it with eeVee now!
I guess you were using Cycles as there is slight noise in the image. The resolution issue I mentioned is only related to Eevee.
As a reference the 8-bits per color channel leaves ridges like in this post: Bump/Normal map leaving ridges?
I can be wrong but I think the bump distance uses blender units so even 0.100 is really huge value for a small detail.
Great character, love the colours and details!
(smack, smack, smack …) “Oooh, how totally gnarly! Really Rad! F’shure!”
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