Newbie question - Artefacts on water-like material using ray

Technical Support Basics & Interface
1

Hello. I’m new to this Forum and hope that someone can help me with a blender question.

“Black holes” appear on my water-like surface and I can’t figure out how to get rid of them.
Take a look www.mahr.cc/temp/palme.png

The water is just a texture on a huge plane (no displacement )

The “Black holes” actually is the background color showing through. So the water is fully tranaparent on some spots where it should just be semi-transparent.

50% of the water material is reflected by ray mirror and the other half is refracted by ray transparency.

The higher I set the normals of the texture, the more areas of the water-surface become “black holes” (fully transparent).

Please help me. - I’m still working my way through the bender manual and yesterday I decided to create this my first full 3D-scene. It took me several hours to build it - and now I am stuck.

lg, Mahrm

2

Both Fresnel values are WAY too high! You probably would be better off with no fresnel at all. Set your IOR value to 1.50 and the depth to 2. Ambient Occlusion can also cause these black faces.

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3

I am geussing from the pic that you have your sky mapped to half a sphere.

When I use a sky mapped to a half of a sphere I will dupicate the sphere then mirrior it along the z axis so the sky maped to it will match the edges of the sphere and blend well.
That usually gets rid of any black spots.

Bet you you have your world color set to black and it is showing through.
Which happens to me when I use AO.

4

Hello.

I tried both, setting down fresnel, as well as mirroring the sphere (and I googled for the term “ambient occlusion” :slight_smile: ) - unfortunately without success. After a lot of trial and error I found out that it was the translucency value of the texture. I moved the slider all the way to the right and suddenly - the black holes were gone.

Nevertheless - thanks for your help, LinkLinker and Fligh.

Here is the final version:
www.mahr.cc/temp/insel3.jpg

lg, mahrm