I am trying to render a platform on the ocean. The mesh of the platform is slightly above the ocean. Considerably enough to avoid overlapping. Do you know why the render shows me the overlapping materials like fading randomly in some spots ? Does the distance to the camera has anything to do ?
Thanks a lot
Edit: I did a render zomning the area and it works perfectly. It seems to be a clipping issue.
Rounding errors are possible which give this kind of effect. But the meshes need to be very close for this to happen. Unfortunately the image is too low-res to confirm.
It might be a clipping issue. Make sure you don’t have a too short Clip Start or too big Clip End .
Depth buffer precision depends on clipping by an exponenial law, meaning if the Clip Start is too short (or Clip End too big) it will be very bad
See you 
++
Tricotou
Unfortunately it does not change when I tweak the ‘‘clip start’’. The strange thing, the viewport does not show changes either. If its not the clip start how to approach ‘‘rounding errors’’ ? not sure what is that.
Thanks
Sharing a .blend would help in that case
Rounding errors means, the computer doesn’t calculate the position of the meshes accurately enough to know which one is above the other. For this to happen the meshes need to be very close. But, yes, I blend file would help diagnose the issue.
Thanks both! I could not share the scene cause it was a file from work 
but I asked in the office and they said it might be EVEE …then switched to Cycles and worked perfectly.
Its a “ocean/water” material with displacements…might be was that. I understand Eevee do not support displacement. I guess was that. Thanks a lot for your help