Aliasing on imported objects.

[Njen]

I have an imported geometry object way in the distance that has crawling aliased edges (see Vimeo link below, top left). Any chance on how to remove this? I've tried a number of things that have had no effect. My Anti-aliasing setting is at 6, do I really need to go higher? I'd rather not as I am about to render a very long shot, I have attached my render settings to this post. I also have buzzing that I'd like to reduce too, though Vimeo compression crushed the hell out of the uploaded video below, it is there.

https://vimeo.com/735048717/6aaef0d43f

I am using 4.6.11 frontier build.
Thanks!

[Dune]

Are you sure it's AA? I also get the impression it might be flickering by reflections on leaves. But it's short and small so hard to see.
Another point; if you want to reduce rendertime for animation, check if you really need a compute terrain. Without one is faster usually, and for 'big landscapes without specific laterals or minimum angle dependent stuff' often not really needed.

[Njen]

Thanks for the response. I certainly do have a computer terrain in the appropriate place, which I have been testing vigorously.

The trees is actually not so big a deal. I could run the frames through a denoiser after it has been rendered. The biggest issue is the anti-aliasing crawling on the structure on the top left. I can't fix that in post.

[Dune]

Ah, now I see what you mean in top left. I only looked at the lower square. Isn't that reflection too? Otherwise I don't know.

[Njen]

I contrasted the image, and can clearly see that the obj reader geo is a lot more aliased than the native planet displaced geo.

[Dune]

Yeah, that's very obvious now. Strange. Maybe it's because of the distance? But it shouldn't be like that.
Btw. something else I noticed, your detail setting is 0.8, which is pretty high (especially for animation I would think). Even for stills I mostly use 0.5, which is very good already. Especially when a lot of the actual planet is covered by objects, it needn't be that high, IMO.

[Matt]

The adaptive anti-aliasing isn't working well in this situation. Changing the first sampling level from 1/64 to 1/16 will probably help, if you need to get this rendered right now. But I'd like to use your object and camera to test with, if possible, and see if I can improve the sampler for cases like this.

[Njen]

The adaptive anti-aliasing isn't working well in this situation. Changing the first sampling level from 1/64 to 1/16 will probably help, if you need to get this rendered right now. But I'd like to use your object and camera to test with, if possible, and see if I can improve the sampler for cases like this.

Hey Matt, thanks for the tip about the first sampling level, that does reduce the issue a lot.

I have attached a cleaned up version of the scene with the object to this reply. Thanks!

[Matt]

I have attached a cleaned up version of the scene with the object to this reply. Thanks!

Thanks for posting this. I did some render tests and I can see the issue. I'll experiment with some ways to improve the sampler.