Infinity Mirror Effect: One Way/ Two Way/ Half Silvered Material

[nathangabriele]

Hi all, I'm trying to achieve a visualization of an effect which is known by several names
>The most descriptive is called the infinity mirror as illustrated here and attached.
https://en.wikipedia.org/wiki/Infinity_mirror
>This is the type of material I'm looking to make
https://en.wikipedia.org/wiki/One-way_mirror

I've attached an image which describes my setup- it is a cylinder that would have the one-way mirror material with an object on the interior to be reflected infinitely.  I also realize that a cylinder probably isn't the best shape, something with flat sides would be better.

Does anyone have experience with such a material?  Or how to create the effect with composite images?

Any help is greatly appreciated.  Thanks!

[Chad Holton]

Hello,

Check out the default scene called "ray_bounces", it is similar to what you're trying to do.

Hope this helps.

Chad

[Will Gibbons]

Interesting question. Short answer to it is, yes. Although I think you may be let down by the results. The difference with the Ray_Bounces sample scene is that instead of your camera being positioned between two perpendicular reflective surfaces, you use a layer of glass in front of a chrome surface (like how a real mirror is made), and the reflection happens between the front surface of the glass and the front surface of the chrome surface.

I created this effect in the first attached example below and it works well. I set the frame to a diffuse color since my light material was incredibly bright to help out with the reflections. 100,000 lumens I believe.

In the second attachment, I've used glass to encapsulate the light source instead of plastic and  a lumen value of 10,000 I believe.

In the third attachment I used the same principal and the internal surface of cylinder was glass and outer surface chrome. I applied a Surface Backside Mask node in the material graph so as to allow us to see through the backside of the chrome surface. Not the prettiest thing, but it works.

I also tried with a half cylindrical mirror in the fourth attachment.

See how to apply Surface Backside Mask here: https://www.keyshot.com/forum/index.php?topic=11378.msg59657#msg59657

Let me know if this is what you had in mind.

[Finema]

very good demo Will 

[Will Gibbons]

very good demo Will 

Thanks!

Here's a better rendering of the one with glass LEDs.

[nathangabriele]

Fantastic!  Thanks a lot Will.   

Could you post a diagram of the material application of the first image (testmirrorII.23)?  This is the best one of the group. 

I'll give it a try over the weekend and post some results.   I think for the purposes of my project, I might have to use several techniques and composite them into one image as it is a bit more elaborate than the original image I posted.  See attached for the actual setup- it involves liquid on the interior of the glass, which is the complicated part.

Again, very much appreciated!

[Will Gibbons]

I've attached the KSP for you to download and play with. I'm pretty sure I've made changes to it since that specific rendering was one of the first ones I created with that KSP, but you should be able to pick this apart and see how it's set up.

It may be obvious, but once you set up your scene, it's going to take a long time to render. I think that unless your goal is to have caustics thrown onto a surface, there's no reason to try to add water, a transparent material to this, unless you're hoping to get lots of refraction.

Also, not sure how you've set up your model, but there's a recent blog pos on the KeyShot website that covers how to properly do liquids in glass. If you're not already aware, I'd check that out.

[nathangabriele]

 You are correct, the idea is to combine the infinite reflection effect with the refractive properties of water- its a bit of an experiment.  Might be easier to just make the real thing as a dirty prototype.

Yep, I am aware of the proper way to render liquid in glass. I followed the tutorial from one of the webcasts a while back. I've been rendering up some liquor bottles and the technique works quite well.

Hey Thanks! I'll play with it over the weekend to see if I can achieve the desired appearance, and post what I come up with. Due to the complexity of the liquid, I'm still anticipating the final result will be a composite.  Will keep you posted.

[bdesign]

Here's my experiment with the infinity mirror. I modeled two solid panes of glass, then extracted the back surface of each, to give me separate geometry for the glass and metallic surfaces of the mirrors. For the mirror in the back of the frame, I used Advanced materials for the glass and metallic surfaces. For the one-way mirror in the front of the frame, I used an Advanced material for the glass, and a Dielectric material for the "transparent metallic" surface. The key with the Dielectric material is to set the Refraction Index to 1.5, and the Refraction Index Outside to .01. This will in effect create a metallic surface on the outside and transparent glass surface on the inside. The Transmission value is set at 95%, and the Color Density at .19. You can control the fade out of the internal reflections with the Color Density value. For my inside/outside examples with the spheres, I set the Transmission value to 100% and the Color Density to 1, to clearly show the transparent/metallic effect. Ray Bounces = 64, Global Illumination enabled.

Eric

[nathangabriele]

Damn, Eric.  That's exactly what I'm looking for.  Thanks for explaining how you did it.

I'm working on a rendering right now, but you guys must have monster machines if you're able to crank them out on short order.  I have a pretty hefty HP ZBook, but its taking a while with these renderings.  I'll post as soon as I have something to show.

[bdesign]

You're welcome, Nathan. Glad to help. I decreased the rendering time drastically by using an Emissive material with the Color, Intensity, and Opacity mapped with Color Gradients, then layered with a clear coat, to simulate a light bulb, instead of using Glass and Area Light materials, and by using the "Make Pattern" tool to create instances of the "lights". Not as realistic as using separate geometry for the glass/lights, but I tried it that way initially and it was impractically slow to render with such an intense amount of reflection/refraction happening.

Eric

[DMerz III]

Wow! Very cool, I want to try this out.

[NM-92]

Eric , you certainly have a wide open mind to solve this kind of thecnical issues. Bravo for that, great solution.

[bdesign]

Wow! Very cool, I want to try this out.

Thanks, dmerziii. Have fun with it

Eric , you certainly have a wide open mind to solve this kind of thecnical issues. Bravo for that, great solution.

Thanks very much for the kind words, Nico. Nice of you to say that

Cheers,
Eric

[Will Gibbons]

Haha! Bravo bdesign. You made my response to this thread seem pathetic, but I enjoy learning every time someone with massive creativity and smarts drops a knowledge bomb like this. Cheers!