LuxCoreRender Forums

There is a gap in the Laser Beam rendering with BiDir, Metropolis.
Infos
BiDir Settings.png
BlendLuxCore.png
Camera Settings.png

Pictures
Fog in Null, cam x 7.94.jpg
Fog in Null, cam x 10.00.jpg
Fog in Null, cam x 11.88.jpg

Rendering the same Scene with Path, Light Tracing doesn't show ...

Image Mutation Rate (IMR)

Same Scene as above.
Metropolis Settings
Large Mutation Probability: 10%$; fix
Max Consecutive Rejects: 1024; fix
Image Mutation Rate: 1..10%, 20%, 40%; variable

Image0001.png
Image0006.png
Image0010.png
Image0012.png
With a low IMR fog in Null material is ...

Large Mutation Probability (LMR)

Fix Settings:
Samples 64
Max Consecutive Rejects 1024
Image Mutation Rate 10%

Scene with a box made from Material Null with Homogenous Volume and IOR of Air. There are three different Lights: red Spot, green Area, blue Area>Laser. The properties of the Area light ...

Hi bartek_zgo

Your renders look to me as if Camera>Tonemapper applied somehow with different settings.

How the three parameters of the Metropolis Sampler influence rendering.

Max Consecutive Rejects (MCR)
Halt Condition: 64 Samples
Materials: Clear Glass, Rough Glass, Homogenous Glass
Lights: Area, 0.01^2
Image0001.png
Image0003.png
Image0005.png
Image0007.png
Image0010.png
Disadvantage ...

CodeHD wrote: Thu Jun 05, 2025 7:36 pm Or could it be something introduced with version 2.10?

No. This behavior is quite old. I guess it never got fixed. If one rendered a messed up frame there was a good chance the second time the same frame rendered okay.

daros wrote: Wed Jun 04, 2025 12:17 pm details for each, architect, render artist, and so on.

Hi daros
Some of the rendered pictures are really overwhelming..
I wonder how many people and work hours are involved to create such detailed scenes.
Regards
fw

Another note: This kind of setup doesn't require BiDir Engine to work.
The result should be mostly the same when using light tracing - at least as far as the directly visiable beam is concerned.



Well, for some setups it makes quite a difference whetter one uses BiDir or Path with Light ...

I don't see anything in the scene you attached that is a significant difference to my scene. Anyways, you noticed the general point I was making, so I guess we are on the same page.

I agree mostly. I don't understand your Camera settings. With your scene Final Render renders only a tiny square ...

Strange Discussion because here a typical Prism render looks well:
https://forums.luxcorerender.org/viewtopic.php?t=6105

A glass that has almost no effect, just enabling/disabling the dispersion mode. File attached


I did not understand your attached scene ..

I setup a scene with 15 thin ...