glass problem

[friscokid]

Hi,
I'm pretty new to octane and have some problems with the glass/specular material.
The images show my first render with octane and as you can see, I'm struggling to setup the glass, so that it doesn't darken everything below extremely.
In the first image I've removed the glass from the watch and this is how the colors and the lights of the clock-face should look like.
In the second image I've added the glass and everything is darkened a lot as if the material was semi-transparent or did absorb the light.

I'm using a pure simple specular material with an IOR of 1.53, rendered with Pathtracing.
What am I doing wrong and how can I setup the glass material so that it doesn't absorb the light or darkens the objects below?

Thanks for your help.

glass removed, lights ok

glass added, lights to dark

[manos]

I think glass ior is 1,32...

[friscokid]

According to Wikipedia and the octane manual the IOR of glass is about 1.52 / 1.53.
But the IOR setting in octane doesn't make any difference regarding the darkening / absorbtion.
It's the same problem with any IOR I tried.

Any other idea what could make the glass material make absobing the light?

[mib2berlin]

Hi friscokid, glass work only right with pathtracing or PMC not with Direct Lightning Kernel.

Cheers, mib.

[Refracty]

he told he was using PT.
What kind of lighting did you set up?

[manos]

Maybe your planes of your glass , and particular the inside plane , are facing the the wrong way... If your glass has a some depth of, let's say, 2 mm , delete the inside plane and see if that is making any difference ??

[friscokid]

@Refracty:
Yes, I'm using PT.

My lighting setup is hdri environment (studio map) combined with two simple blackbody emitter planes.
But the problem persists even if I disable the emitters or use another hdri map.

All the lighting seems to be correct as long as no glass is in the scene.

@manos:
The glass is not a plane but is an object of about 0.8mm
I checked the normals and they all point correctly to the outside of the object.
To model a realistic watch glass, I can't use a plane, because it would look flat and the refraction effects at the border would be missing.

[ROUBAL]

I think that you will have to cheat a bit and use an opacity value around 0.4 maybe...

[mib2berlin]

Huh, sorry overread PT.

Mib

[Refracty]

is the max depth in the kernel settings high enough? I think 8 should be more then enough and the standard value is 16 but just to be sure...