I were doing some test renders using Superfly and had/have some problems with noise or artifacts in the renders, which are pretty annoying :) However I started doing some testing, as it at least to me seems that there are some weird issues with the PhysicalSurface node when it comes to roughness. So i made a test scene with a Box and a tile material linked to the metallic and roughness with one tile being black and the other white. In front of the box is a single point light with ray trace shadows. The material look like this:

First render:

Looks to be correct the light gets reflected in the tile but not the one underneath.

As the light is moved down so it around the edge between the two tiles, noise or artifacts starts to appear around the edge.

As the light is "behind" the non reflecting tile, its clear that some noise appear where the point light is.

So i tried to increase the roughness from 0.1 to 1, which had little effect.

Next i raised the pixel samples to 40, to see if that could fix it, (Took around 10-15 minute to render) But did nothing to remove it.

So I tried to unlink the tile map from the roughness and just use the same roughness for the whole object.

This seems pretty weird to me, that the hotspot of the light reflects where it shouldn't and it looses intensity as it gets close to edge of the reflective tiles where it then regain its intensity as it is reflected.

To me something seems to be wrong, especially the white noise that is created and even with 40 pixel samples its still there. If this were an actual scene with reflective objects scattered around. The amount of noise could be quite a lot with practical, as i see it, no way to fix it.

Does anyone have an idea whats going on here or whether its a bug or if im missing something?

Did some more testing and it seems you have to reverse the roughness map. :)

These are some great observations! Thank you for sharing them with us!!

How did you reverse the roughness map?

| These are some great observations! Thank you for sharing them with us!! |

Unfortunately, I had hooked up the roughness map wrong in the test...Dohh!! :D However guess it could help someone that experience such issue, that it could be due to their roughness map being wrong.

| How did you reverse the roughness map? |

I just copy pasted the tile map and switch around the black and white tiles. However just to be clear it doesn't mean that the roughness map should always be inverted, it was just in my test. The more rough you want a surface to be, the more white it has to be in the roughness map, so 100% roughness equal white and 0% roughness is black.

However this test did little to solve the noise problem as it seems to come from somewhere else. So I now suspect that its the lights themselves in Poser. So did some more testing, that hopefully ain't flawed :D

This is from the actual scene where im testing. There is one point light placed a little bit underneath the ceiling (Hotpot in the ceiling shows approximately where)

First image have 100% intensity and looks sort of what you would expect with such bright light. There are a little noise but its rendered at 10 Pixel samples.

Second image is at 50% intensity, still looks somewhat ok, however some problems starts to occur i think.

Third image is at 10% intensity, now i think some problems really starts to show. Looking at the ceiling and the floor the light is very dim. However the edge of the window is still very lit and the reflection on the machine to the right looks like its a 9000 Watt light bulb hanging there and doesn't seems to really match the amount of light that is on the floor or even the ceiling to which the light is much closer to.

Fourth image the intensity is 1%, still the window is very bright compared to the intensity of the light and even though the reflection in the machine is not as bright it still seems to bright, i think.

To me it seems as if the light intensity falloff is some what off when it comes to reflections or is it just me?

Is it possible that you have an infinite light on? Are you using IDL or IBL lighting setup?

Is it possible that you have an infinite light on? Are you using IDL or IBL lighting setup?

Dammit, noticed the window was a little misplaced :D So ignore that. However the reflection on the machine is still the same. But the point light is the only light in the scene, and uses these settings..

Here is the 10% intensity with corrected window just so you can see what to ignore.

Can you re-render it without the Ambient Occlusion enabled? I thought that was a throwback to when we didn't have IBL or IDL. Also what happens if you unchecked "Visible"?

I tried to render it again without ambient occlusion and with the light invisible. It have no effect it looks exactly as the image above. However I tried to recreate the scene in 3ds max as best i could, converting the scene 1 to 1 is not easy as it uses some other settings. But I tried to match the camera view as best as I could and added a single photometric point light approximately where it is in Poser scene. This turned out to be quite interesting i think and beyond my technical understanding of how these things works, but hopefully someone with such knowledge or idea can help explain it.

Since these photometric lights works differently than those in Poser, I made the light at 750 cd intensity which will be equal to the 100% intensity in Poser. Also all images are rendered for 4 minutes.

Light intensity of 100%

Light intensity of 50%

Light intensity 10%

Light intensity 1%

I think its pretty clear that the light is much more natural, the reflection seem to match the intensity of the light. So at first I thought that this is a problem with Poser then. But to be honest, it took me quite a long time to get the light looking correctly.

This is a render with the exact same lighting and everything as the 10% intensity image above, Only differences between them is that i turned off Gamma/lut correction in 3ds max, the same option you have in Poser render settings for Firefly, but not for Superfly so I cant test it in Poser.

But if you compare the Poser renders with this image, despite that the lighting works a bit different. They share the same weird hotspot, but also compare the noise between the 10% 3ds max renders without the gamma correction and this one, both of them have rendered for 4 min which can be setup in max. Its really weird that the difference is so severe. Can anyone explain what is going on here? Why does Gamma/Lut correction have such huge impact on render quality in PBRs and is there a way to turn it off for Superfly so I can test it there?

Problem solved :D

Even though im still not sure why the gamma/lut causes problems. It seems to be possible to fix it by setting all materials when loaded to a custom gamma of 1.0 Whether that is a rule of thumb or only if you are using jpgs i don't know. But if anyone can explain it, i would appreciate it as its always good to know why you have to do something :D

But here is a Poser render with 10% intensity and no Gamma correction.

Hi there

I'm pretty sure SuperFly can be used only with Gamma Correction and Gamma Correction is what we are see and is correct way how to render,same can apply for FireFly and IDL,you should render with IDL and gamma correction is well worth it

in yours case I would suggest,did you used BB EnvSphere or EZDome,if not I would use this and regarding the weird hotspot,this is what I found out few months and few days back again

I would suggest to use area light and try aim light on floor or use -90 and use large scale for light,usually is big as ceiling or you can try to use other lights,but with spot light or any other light you will see this hot spot,but same can apply for area light as well,other option is to use mesh lights

Hope this helps

Thanks,Jura

jura11 posted at 10:27AM Thu, 30 March 2017 - #4300864

Hi there

I'm pretty sure SuperFly can be used only with Gamma Correction and Gamma Correction is what we are see and is correct way how to render,same can apply for FireFly and IDL,you should render with IDL and gamma correction is well worth it

in yours case I would suggest,did you used BB EnvSphere or EZDome,if not I would use this and regarding the weird hotspot,this is what I found out few months and few days back again

I would suggest to use area light and try aim light on floor or use -90 and use large scale for light,usually is big as ceiling or you can try to use other lights,but with spot light or any other light you will see this hot spot,but same can apply for area light as well,other option is to use mesh lights

Hope this helps

Thanks,Jura

This weren't meant as exercise in how to light a scene, but to simply solve a problem of light being wrong, so I wanted to keep the scene as simple as possible to avoid having to troubleshoot several things at the same time. If you compare the last image rendered in Poser with the one rendered in 3ds max using the same intensity, they look very similar, which to me indicate that the problem is not the lights themselves but actually the gamma settings of the materials, which is crucial or very important i think. Because you might end up adding a lot of lights that ain't needed or might try to change a lot of Superfly render settings in order to solve some issues which have nothing to do with these things. The last image is rendered at only 15 pixel samples which ain't that much, but even at this setting the amount of noise compared to the 10% render with wrong gamma is a lot less, especially if you compare the noise in the highlights and this is also the case even if I render the image at the same 10 pixel samples settings as the other one.

Which is why i think its very important information to be aware of, because if you render an image and you see noise here and there, but are not really aware of this issue, you might look at the obvious solution of simply increasing the pixel sample to 40 or something in hope that it will solve it, but it wont as the noise is added due to the materials being wrong which in the end will affect the whole scene regardless of the amount of pixel samples. Besides that, being able to work at low pixel samples will greatly increase render speed, which everyone likes :D

Im a huge fan of the PhysicalSurface root node, because its so easy to work with, some people are very good at creating all these shaders, with multiply, blending and all these different things you can add together, which i have never really been that good at, I can make some basic things, but don't find it very easy to make them and get the effects i want. The PhysicalSurface node works very much like other PBR render engines does in other applications like 3ds max, substance painter etc. simply by using these Metallic/Roughness settings.

This is the render settings from 3ds max, its even simpler than the Superfly settings, at least to get started you just crank up the slider :

Here you have a simple glass, no crazy things with nodes all over the place trying to fake this and that, its just very simple settings, so at least to me this is a huge benefit.

(Sorry the quality is bad, i grabbed it from a youtube video :D)

But as shown in the image from 3ds max that i rendered above with the Gamma/lut enabled, it doesn't matter how much you increase the render quality, it still looks wrong if the materials applied to the objects are incorrect. And agree with you that setting up light you could use all these HDR maps, domes and so forth to make the lighting cool, but this will help little if the materials are screwed i think. Anyway this post is getting rather long :D