Striations on final image

[JamieN]

I am getting some weird striations on my final image. I have no physical lights and using the startup hdri. Anyone know what might be causing this?

[guest84672]

Hard to say what is going on. Is that in 6 or 7?

[JamieN]

This is in 6.3

[INNEO_MWo]

 Does the bottom part material has any bump or normal texture applied? Then try to reduce the depth value a bit.
I guess you run full simulation lighting preset?
Use a simple one. No caustics, no global illumination, just simple 6 ray bounces.

Hope that helps