Corona v1.3 vs 1.7

[Ludvik Koutny]

No, adaptivity works the way it should. It's just not right to assume adaptivity means faster rendering. What adaptivity does is ensuring the rendered image converges more evenly.

You can see that on Cecofuli's second test. Compare 1.7 adaptivity on and adaptivity off columns. You can see that adaptivity off makes area around the door and chair cleaner, but area in DoF and area where the bronze sculpture touches the floor noisier. Adaptivity on makes noise level roughly the same across the entire image, so area around the door and white chair has about the same amount of noise as the area around the sculpture touching the floor and scultpure in DoF.

Practical way to think about it is following:

Previously, when Corona did not have adaptivity, you would render your image for 1 hour, and it would be quite clean, but there would be a few hotstops of noise, which would take many more passes to resolve, so to get completely and evenly clean image, you would need to wait 4 hours.

Now that Corona has adaptivity, after that 1 hour, you may get an image, that is more noisy on the areas where adaptivity off was cleaner, but less noisy on the areas where adaptivity off was a lot noisier, so instead of taking 3 more hours, it may now take just 1 hour to get completely clean image. Therefore, to achieve relatively noise-free image, without any hotspots of noise, it can now take just half of the rendertime. Sometimes more, sometimes less, but generally, it's significant improvement.

[lacilaci]

No, adaptivity works the way it should. It's just not right to assume adaptivity means faster rendering. What adaptivity does is ensuring the rendered image converges more evenly.

You can see that on Cecofuli's second test. Compare 1.7 adaptivity on and adaptivity off columns. You can see that adaptivity off makes area around the door and chair cleaner, but area in DoF and area where the bronze sculpture touches the floor noisier. Adaptivity on makes noise level roughly the same across the entire image, so area around the door and white chair has about the same amount of noise as the area around the sculpture touching the floor and scultpure in DoF.

Practical way to think about it is following:

Previously, when Corona did not have adaptivity, you would render your image for 1 hour, and it would be quite clean, but there would be a few hotstops of noise, which would take many more passes to resolve, so to get completely and evenly clean image, you would need to wait 4 hours.

Now that Corona has adaptivity, after that 1 hour, you may get an image, that is more noisy on the areas where adaptivity off was cleaner, but less noisy on the areas where adaptivity off was a lot noisier, so instead of taking 3 more hours, it may now take just 1 hour to get completely clean image. Therefore, to achieve relatively noise-free image, without any hotspots of noise, it can now take just half of the rendertime. Sometimes more, sometimes less, but generally, it's significant improvement.

Well, that's what I thought. Just got a little confused with these comparisons against 1.3 i guess...

However, did a little "tweak" to Cecofuli's scene to exaggerate the adaptivity on/off difference by adding a complex object (Oats's Zygote) with close to a hundred 4K UDIM textures loaded through max's composite node. Throwing the balance of complexity on screen a bit more off...

The results are as expected, however I have to say it seems to me that the clarity on the creature doesn't seem that much better with adaptivity, while everything else is much more worse...

PS: off topic but is there a better way to load UDIMs?

[maru]

Maybe with the v1.7 we can use a stronger Filter Width to blur a bit the noise, like in the v1.3 =)

There is blur/sharpen in the VFB post tab for this.

(Oats's Zygote)

Wait, where did you get this model from? o_o

[lacilaci]

Maybe with the v1.7 we can use a stronger Filter Width to blur a bit the noise, like in the v1.3 =)

There is blur/sharpen in the VFB post tab for this.

(Oats's Zygote)

Wait, where did you get this model from? o_o

Steam... there is also rivergod from firebase and klum from rakka... + lots concepts, scripts and whatnot. Look it up...

[TomG]

And shouldn't denoising also be factored in? The biggest purpose for adaptivity that I see is to allow denoising to do its magic, and that saves a lot of render time.

[cecofuli]

Maru, I think (but I'm not 100% sure) that Filter width is different that from Blur/sharpen.
Blur/sharpen is a post-production tool, and Filtering is something who works at sub-pixel level.

About denoising, my test was intended to compare the quality of noise between the last Corona version.

[vkiuru]

No, adaptivity works the way it should. It's just not right to assume adaptivity means faster rendering. What adaptivity does is ensuring the rendered image converges more evenly.

You can see that on Cecofuli's second test. Compare 1.7 adaptivity on and adaptivity off columns. You can see that adaptivity off makes area around the door and chair cleaner, but area in DoF and area where the bronze sculpture touches the floor noisier. Adaptivity on makes noise level roughly the same across the entire image, so area around the door and white chair has about the same amount of noise as the area around the sculpture touching the floor and scultpure in DoF.

Practical way to think about it is following:

Previously, when Corona did not have adaptivity, you would render your image for 1 hour, and it would be quite clean, but there would be a few hotstops of noise, which would take many more passes to resolve, so to get completely and evenly clean image, you would need to wait 4 hours.

Now that Corona has adaptivity, after that 1 hour, you may get an image, that is more noisy on the areas where adaptivity off was cleaner, but less noisy on the areas where adaptivity off was a lot noisier, so instead of taking 3 more hours, it may now take just 1 hour to get completely clean image. Therefore, to achieve relatively noise-free image, without any hotspots of noise, it can now take just half of the rendertime. Sometimes more, sometimes less, but generally, it's significant improvement.

Well, that's what I thought. Just got a little confused with these comparisons against 1.3 i guess...

However, did a little "tweak" to Cecofuli's scene to exaggerate the adaptivity on/off difference by adding a complex object (Oats's Zygote) with close to a hundred 4K UDIM textures loaded through max's composite node. Throwing the balance of complexity on screen a bit more off...

The results are as expected, however I have to say it seems to me that the clarity on the creature doesn't seem that much better with adaptivity, while everything else is much more worse...

PS: off topic but is there a better way to load UDIMs?

Wait, so all this time adaptivity may have actually been making images noisier, overall? I guess it's my own fault for taking it for granted, and not reading more/doing tests but I just thought adaptivity would add more samples to areas where they were needed - but this tradeoff doesn't seem like a good deal at all if the comparison renders here are correct :O

[FrostKiwi]

I just thought adaptivity would add more samples to areas where they were needed

No, you thought correctly. Adaptivity is Gold if you have the Enviroment texture visible. With no adaptivity you would be non stop sampling the enviroment, although it never actually needs to be sampled, thus wasting power. All in all it almost always worked great with what it did.

For me Adaptivity fails with being too sensitive sometimes. For instance here.
Although it's about caustics it still holds true for some interiors. Noise is most visible on non textured uniform surfaces - i.e. Walls. There Noise pops out very strongly. But technically the Noise is not "more" there. It just is very visisble compared to a blank solid wall.
For many interior scenes with glossy surfaces near windows, the reflection of the glossy surface gets over 10x the processing power compared to the wall.
But the reflection of the glossy surface is barely visible even though it may have high noise levels. But the Solid color wall with maybe only 3% noise is still apparently noisy, but won't clear out until 500passes, because that reflection of the glossy surface gets everything.

Yet still Adaptivity works fine in most other cases.

[cecofuli]

In my test, there is a big glossy column inside a DOF area.
Try to render this scene for 1 hours (not 5 minutes) with:

Adaptivity OFF : very clean white wall, but the noise in the DOF is too much, compared to the rest of the scene
Adaptivity ON: wall is a bit noisy, but the noise is more uniform and pleasant.




 

[vkiuru]

I just thought adaptivity would add more samples to areas where they were needed

No, you thought correctly. Adaptivity is Gold if you have the Enviroment texture visible. With no adaptivity you would be non stop sampling the enviroment, although it never actually needs to be sampled, thus wasting power. All in all it almost always worked great with what it did.

For me Adaptivity fails with being too sensitive sometimes. For instance here.
Although it's about caustics it still holds true for some interiors. Noise is most visible on non textured uniform surfaces - i.e. Walls. There Noise pops out very strongly. But technically the Noise is not "more" there. It just is very visisble compared to a blank solid wall.
For many interior scenes with glossy surfaces near windows, the reflection of the glossy surface gets over 10x the processing power compared to the wall.
But the reflection of the glossy surface is barely visible even though it may have high noise levels. But the Solid color wall with maybe only 3% noise is still apparently noisy, but won't clear out until 500passes, because that reflection of the glossy surface gets everything.

Yet still Adaptivity works fine in most other cases.

Ah gotcha. Thanks for clearing that up and the info here is something that is good to know in future scenarios.

[cecofuli]

New test, with the last v1.7 RC3.