Need help with strange pixels

[emendix]

Hello,

i got a strange problem and was hoping somebody know what to do because i have no idea how to fix that issue. It is quite easy to reproduce:
Load any character in Poser . In my example it's one of my V4 characters. Then create a ball prop and place it anywhere (in my example in the face) and let it poke through. Then set it's opacity to 0.0 in octane. I would expect the ball to be completely invisible but take a look what happens:

Strange opacity pixels in octane

You maybe want to know in which situation this could become important: I have a Hair prop that uses a cap with an transparency map. On some places the cap pokes through the head but it should not matter because it is 100% transparent at this places because of the transparency map. It renders nice inside Poser's Firefly engine but octane shows this strange black pixels. How can i get rid of that?

Edit: The character has no shader applied. Just the default one from the Poser Plugin. I've tried to change the face material to diffuse and remove any bump or other extras but nothing changed.


Thank you very much for any help!!

Manuel

[TRRazor]

The problem you have is self shadowing vertices of the geometry of the ball prop (hair prop) with the character you're using.
Solution for hair: Enlarge the hair prop so it doesn't poke through the characters head anymore and you will get rid of the shadows.

Alternative: Scale down the "rayepsilon" value in the "kernel" settings of OctaneRender - it will slightly increase your render time but it can get rid of most of the self shadowing.

BTW: What exactly are you trying to achieve by placing a ball inside a characters head? Trying to make it glow?

PS: To answer your question why the "pixels" are still visible - even though you turn down the opacity to zero. That's an easy one: The geometry is still in the scene, the opacity just makes it invisible for rays passing through it - that doesn't mean though that it's not "physically" still in the scene

Hope I could help

[face_off]

Alternative: Scale down the "rayepsilon" value in the "kernel" settings of OctaneRender

A rayepsilon of 0 will generally fix this, and the same issue with eyes.

Paul

[samhal]

Alternative: Scale down the "rayepsilon" value in the "kernel" settings of OctaneRender

A rayepsilon of 0 will generally fix this, and the same issue with eyes.

Paul

Yup, ditto!! Fixes most problems of these types.

[emendix]

Great! Thank you very much! Thats working fine.

BTW: What exactly are you trying to achieve by placing a ball inside a characters head? Trying to make it glow?

The ball was just for a demonstration so others can reproduce this effect easily. As is sayed i had this effect because of a not perfectly fitting hair cap

You helped me alot! Thank you, thank you, thank you and have a nice day!
Manuel