Hello there!
I have this issue with a surface not being rendered perfectly…
I used Blender 2.79 - Cycles - Principled BSDF + A lamp (Sun - Strength 10) + A 4k hdri as an environment texture) + 1024 Samples for rendering.
As a .png the lines are less visible and more visible as a .jpeg
I tried using a Subdivision surface, even a different shader (Glossy BSDF).
Thanks!
Looks like color banding: https://en.wikipedia.org/wiki/Colour_banding
You need to change dithering slider to 1 or 2: https://docs.blender.org/manual/en/2.79/render/post_process/panel.html#dithering
Wow, this is it, thank you very much!
From what i see, it also affects the overall brightness of the materials but this can easily be solved with compositing or an external app.
