Reflected light doesn't show up behind glass? SOLVED


I made a kinda lens but wich has a height diffrence between light entry and exit. So I made 2 mirrors in between rotated at 45° to make up for the height diffrence (cfrperiscope).
Trouble is, it seems that my lenses don’t allow reflected light to pass.
So when I use a light source that has to pass the 2 mirrors before reaching a lens it won’t pass the lens. When I just put up a light source it passes the lens no questions asked.

I made a little collage:

In made a setup with my glass only covering half of the hole hence you can see half of the pink suzanne wich is reflected by the 2 mirrors in the part not covered by the glass. And you can see a blue emitting mesh that was placed after the mirrors but it is visible behind the glass.

Some explanations,
the color blobs show wich material was used.
Black material has a shader that doesn’t allow light to pass nor to reflect (hence its black)
Pink and Blue materials are just normal materials but with a 100%Emit.
Green is my lens glass
Light Blue is a 100%mirror.
All of them are double sided.
The yellow arrow shows how light emitted by suzanne should go.

So how comes BI doesn’t allow this? Or is the fault mine?

Thank you for your time

might have to bump up the depth on the ray trace, which is the number of times something can reflect or the number of bounces that a ray can take. default is 2 which is not enuf for your rig.

Myes, but no. I’m not raytracing. I’m using Blender Internal (with ray tracing enabled but that doesn’t have a depth button). And I increased the ray mirror depth of the mirror to 5 but to no avail. I allso tried adding a sun with ray shadows but no diffrence.
(or is what you want something else?)

you are raytracing if you have clicked Ray in the Render panel. Enabling ray tracing in the render panels means that Blender will honor the raytracing material settings:

change your things that Emit 100% to lamps that are those colors. Lamps put out colored light. emitting objects only radiate.

Hmm . . . I’m not sure why you’re having problems. I’ve set up a scene based on your screenshot, and it works fine for me. Whether using lamps to illuminate Suzanne, or giving her an Emit factor, she shows up through all reflections and refractions.

If you post the .blend, I’ll see what it does on my system (maybe find a setting that’s off, too).


It works more or less with a simple setup (as in the collage) but in my lens not.

.blend (rapidshare)

And you may even try to guess what it is it’s allmost done. (the materials s*** cuzz I s*** at materials).

Thank you for the help

Got it to work . . . here’s what you do:

On the mirror material, you don’t need a high depth (it still works at 0) . . . but you do need to increase the ray depth of RayTrans in the glass/lens material to at least 5.

Not sure if it’s necessary (because I did this first), but you should separate the reflecting/refracting meshes from the ones with standard materials. When you want semi-realistic light behavior, it’s best to model objects as accurately as possible. Any connection or overlap of meshes may affect the resulting effects of reflection and refraction.


I’m assuming you want Suzy to show up through the lens, correct?

I bumped up the RayTrans depth on your glass lens by one. Actually, at first, I maxed it out. Then, instead of fixing a loose nail with a jack hammer, I decided to try again, increasing the depth by just one. Afterwards, it rendered fine…I think. I got Suzy to show up through the viewer, anyway.

Hope this helps.

If you’re using ray trans on the lens then you don’t need any depth on the mirrors, the ray trans will take care of the effect for you as long as you have ray trans set at 2 or higher.

Thanks everybody for their time and help. Suzanne shows up. In attachment Suzanne doin whatever she allways does from behind the lens.

A mod can close this thread if needs be.