Plastic Bottle issue

[gieroj]

hey guys,

i'm having a problem with some dark spot on the top of a sprite bottle. I suck at modeling so this might be a simple issue. The bottle has thickness.

Removing the liquid seems to help reduce the black area at the top. Fake shadows are checked.

I am using a 1.21 IOR for the bottle, as it seemed to give best results. Droping IOR to 1 obiously removes the black spot.

Octane version: V4.05-R7
C4D version: R18

1. The model: https://www.turbosquid.com/3d-models/we ... el-1309349

2. Renders are attached.

3. Octane settings tab is also attached

4. Scene file attached.

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Does anyone know how to fix this?

Would be much appreciated.

thank You

[hausgross]

I couldn't take a into the scene file (is it attached?) but from the look of your render and the images on Turbosquid I'd say it is an issue with the model.
My guess would be flipped normals or unconnected polygons on the inside of the bottle. Try "Optimize" or adjusting the normals and see what happens. You could also try out different "Ray Epsilon" values in the Octane settings, this can have a great impact on refractions.

Also the liquid should clip a tiny bit through the inside wall of the bottle.

[gieroj]

thanks @hausgross.

seems like the model is bad.

i tried Your suggestions. Only changing the Ray epsilon value seems to work, but to elimate the black spots, i have to push it soo far, it destroys my scene. No liquid is visable.

I also tried the Mesh Checking feature and figured out that there are some issues with that too (Not Planar Polygons). Screens and scene here: https://www.dropbox.com/sh/y242lbp11udi ... J7-2a?dl=0

The most difficult parts seems to be the most curved area near the cap.

[hausgross]

Hi,

had some minutes to look at the file. There was a mesh for the liquid inside the bottle that caused the issue. Without the liquid from the model, a proper thickness and some ray epsilon settings the model looks fine.

[gieroj]

Yes, that's it! @hausgross

Thank You sir!