Noise problem on glass (ART render)

[Anonymous]

I want to make a scene composed of several layers of glass, one behind the other. It has to be as realistic as possible.

When rendering, the transparency of the glass is transformed into noise that accumulates in each layer.

Does anyone have any idea how to improve this?

[Anonymous]

I want to make a scene composed of several layers of glass, one behind the other. It has to be as realistic as possible.

When rendering, the transparency of the glass is transformed into noise that accumulates in each layer.

Does anyone have any idea how to improve this?

[Anonymous]

You have set the render quality low in the render setup window. Increase the quality. If you think it takes too long you an stop the render without losing it.

Also enable the noise filter.

That glass with multiple layers is a challenge for art renderer but you will get better results if you increase the render quality.

Art render can be quite slow in some conditions, it has not the flexibility of customisation of other render engines.

After 5 minutes of render compared with your version

draft qualityhigher quality+noise reduction 5 minutes in a i7-6900k

[Anonymous]

You have set the render quality low in the render setup window. Increase the quality. If you think it takes too long you an stop the render without losing it.

Also enable the noise filter.

That glass with multiple layers is a challenge for art renderer but you will get better results if you increase the render quality.

Art render can be quite slow in some conditions, it has not the flexibility of customisation of other render engines.

After 5 minutes of render compared with your version

draft qualityhigher quality+noise reduction 5 minutes in a i7-6900k

[Anonymous]

Thanks KarlAkimor!

Yes the noise is improved especially with the noise reduction, but there is still something in between the layers, and the transparency is lost. I've tried increasing the quality, changing the scale, adding some lights, but there is no significant change. The noise doesn't disappear.

Do you know another render engine best designed for achieving a real-physical result? (e.g. Mental ray with special material setting for glass?)

I've tried with vray and occurs the same.

[Anonymous]

Thanks KarlAkimor!

Yes the noise is improved especially with the noise reduction, but there is still something in between the layers, and the transparency is lost. I've tried increasing the quality, changing the scale, adding some lights, but there is no significant change. The noise doesn't disappear.

Do you know another render engine best designed for achieving a real-physical result? (e.g. Mental ray with special material setting for glass?)

I've tried with vray and occurs the same.

[Anonymous]

Avoid Mental Ray, it is an obsolete engine and is OK only for people that has lots of experience with it.

I recommend Arnold that is integrated with Max 2018 and available for 2017. It is as high quality as it can be, used by films as standard and a lot better than Art renderer.

Vray is good if do a lot of architecture visualisations because it has lots of tricks to optimise speed, but is a lot more complex and confusing to use than Arnold, a bit less visual quality and you need to buy it separated. Arnold can be slow with no direct light when Vray is fine, something that a film studio won't mind as they have huge render farms. If you had problems with vray is because you didn't find the setting to change, and that is the problem of Vray, a very step learning curve. But it can literally optimise anything.

Keep in mind those overlapping glasses are going to be a challenge for any renderer that pretends to be physically accurate, but when other renderers can deal with it Art can find easily dead ends where speed is simply not practical.

[Anonymous]

Avoid Mental Ray, it is an obsolete engine and is OK only for people that has lots of experience with it.

I recommend Arnold that is integrated with Max 2018 and available for 2017. It is as high quality as it can be, used by films as standard and a lot better than Art renderer.

Vray is good if do a lot of architecture visualisations because it has lots of tricks to optimise speed, but is a lot more complex and confusing to use than Arnold, a bit less visual quality and you need to buy it separated. Arnold can be slow with no direct light when Vray is fine, something that a film studio won't mind as they have huge render farms. If you had problems with vray is because you didn't find the setting to change, and that is the problem of Vray, a very step learning curve. But it can literally optimise anything.

Keep in mind those overlapping glasses are going to be a challenge for any renderer that pretends to be physically accurate, but when other renderers can deal with it Art can find easily dead ends where speed is simply not practical.

[Francisco_Penaloza]

Your problem is how far your ray will travel, most advanced raytracer engines, Such V-Ray, Arnold, Mental Ray and other have the option to adjust how far the ray will travel through glass or other transparent objects.

In your case Art render does not have this option, you can try changing to Advanced Path tracer, but I am not sure if that will solve it, also the render time will increment will be considerable.

@Anonymous

I am sorry but I don't agree with what you mentioned about V-Ray, as up to dayArnolds is as complex to use as V-Ray and in reality at is core with the new V-Ray you only need to controls 2 settings, nothing else for most images or animations, Arch Viz, product Viz or VFX.  Where with Arnold you need to setup Diffuse bounces, Speculars, and others.

 There are other differences between these two render engines, but they can't not be simplified as, this one is simpler than the other one.

[Francisco_Penaloza]

Your problem is how far your ray will travel, most advanced raytracer engines, Such V-Ray, Arnold, Mental Ray and other have the option to adjust how far the ray will travel through glass or other transparent objects.

In your case Art render does not have this option, you can try changing to Advanced Path tracer, but I am not sure if that will solve it, also the render time will increment will be considerable.

@Anonymous

I am sorry but I don't agree with what you mentioned about V-Ray, as up to dayArnolds is as complex to use as V-Ray and in reality at is core with the new V-Ray you only need to controls 2 settings, nothing else for most images or animations, Arch Viz, product Viz or VFX.  Where with Arnold you need to setup Diffuse bounces, Speculars, and others.

 There are other differences between these two render engines, but they can't not be simplified as, this one is simpler than the other one.

[Anonymous]

To be honest I have not played enough with the last version of Vray, so you could be right. In the past Vray has been always very complex when optimising speed. But at then end this was also his advantage because with so many settings you always were able to find a compromise between speed and quality suitable for personal computers. I'm not sure if Arnold can do the same to that level, specially with indirect light.

[Anonymous]

To be honest I have not played enough with the last version of Vray, so you could be right. In the past Vray has been always very complex when optimising speed. But at then end this was also his advantage because with so many settings you always were able to find a compromise between speed and quality suitable for personal computers. I'm not sure if Arnold can do the same to that level, specially with indirect light.

[Anonymous]

Many thanks @Francisco_Penaloza

Yes I suspected that was the problem, but I can not find a way to solve it.
I have set up the scene with Vray, I have tried with the settings to the maximum (global illumination, irradiance map) but the "blessed" noise still appears between the layers.

I attach a screenshot and the file.

[Anonymous]

Many thanks @Francisco_Penaloza

Yes I suspected that was the problem, but I can not find a way to solve it.
I have set up the scene with Vray, I have tried with the settings to the maximum (global illumination, irradiance map) but the "blessed" noise still appears between the layers.

I attach a screenshot and the file.

[Francisco_Penaloza · Accepted solution]

Noise is a different problem than opaque translucency.

If you are using V Ray 3.x reset everything to default, progressive rendering will render only for 1 minute, this may not be enough time to clean your scene, you can give more time and see if that helps, otherwise switch to bucket mode and test.

In this specific scene, you have too many transparent objects in front of each other, this is not common, in this case count how many faces you have, let say they are 10 boxes so you have 20 planes with transparency, in that case, go to Global switches and check the box override depth, default is 5 change that to 21 (my example) that should fix the tracing issue.

The noise just samples, that's not related to transparency.

[Francisco_Penaloza · Accepted solution]

Noise is a different problem than opaque translucency.

If you are using V Ray 3.x reset everything to default, progressive rendering will render only for 1 minute, this may not be enough time to clean your scene, you can give more time and see if that helps, otherwise switch to bucket mode and test.

In this specific scene, you have too many transparent objects in front of each other, this is not common, in this case count how many faces you have, let say they are 10 boxes so you have 20 planes with transparency, in that case, go to Global switches and check the box override depth, default is 5 change that to 21 (my example) that should fix the tracing issue.

The noise just samples, that's not related to transparency.