Help with AntiAliasing geometry

[Danielhruby]

I need some help improving antialiasing of this light fixture. note the black jaggies along the glowing part of the lamp bulbs. The rest of my scene looks OK, but this light is a persistent problem. II thought maybe the issues is related to having a very bright light source next to the metal fixture housing. I have tried a couple ways of setting up the light. 1) Luminous ploys + multiplier tube lights. 2) Luminous ploys only 3) Mesh Light with luminous polys. All seem to look terrible, but the best looking lighting is by using the mesh light + minimal luminous ploys to get the light to glow. Otherwise, I am pretty much using the default settings. Image sample is Adaptive and GI is Irradiance and Light cache.

[boyan]

Hey,

Thank you for the feedback, can you send to me the scene file, for testing purpose and workaround.

EDIT: I found the scene file in your previous post, so you don't need to send it.

[boyan]

Hey, Daneil,


The problem is AA filter type, which you've been used with this scene. This is a perfect example of "moire" effect. Change this to "Lanczos" and play with Size or use Area filter.



Cheers,

[sirio]

Keep the normal Vray mesh light and add a little bloom effect, this will cover any AA problem on the high contrast zone. This will not only resolve your issue but it will also improve the realism of the image.

[^Lele^]

Two order of issue there:
a) As Boyan suggested, use non-negative component filters (ie. non-sharpening ones): the default V-Ray Lanczos implementation doesn't have said negative part, so it won't lead to fringing around overbrights.
b) Very bright pixels can't effectively be anti-aliased when next to much darker ones (a light at 30 float, versus a wall at 0.5f, f.e.), and for that you will need to add, as sirio said, a glare effect, and perhaps some bloom. This is how real world sensors (the eye, a camera lens) behave under similar conditions

[Danielhruby]

Thank you. Very helpful.

[tioem]

Hey, sorry for borrowing this thread but I'm probably dealing with something similar at the moment.

Any idea what is causing this? (see attached image)

I've tried experimenting with AA filters, bloom/glare filter and some other stuff but without any success.

The scene can be downloaded here:
https://www.dropbox.com/s/1a0b4wbk4b8goi1/help.zip?dl=0

-t

[Danielhruby]

Without being able to look at your scene, it Almost looks like you have enabled rounded edges?

[tioem]

Rounded edges doesn't seem to be activated. I stripped down the model/scene and pasted everything in to a fresh scene(the one I uploaded in previous post) to avoid as much 'settings-related' issues as possible.

[Danielhruby]

I don't really see any problems. Those look like reflection highlights from your two area lights above. I think that if you are using Sub-D surfaces, you might need to enable Vray SubD on the Vray Geomtry parameters. But I don't see any change after doing that. What is it that you are concerned with? The highlights?

[vladimir.nedev]

I think that if you are using Sub-D surfaces, you might need to enable Vray SubD on the Vray Geomtry parameters.

No, you don't need to do that.
In some situations it could be useful, but generally it's not required.

Greetings,
Vladimir Nedev

[tioem]

What I am looking for is a more smooth (antialiased) edge on the image I attached. Never had this issue before when rendering with Modo's native renderer or vrayforc4d/3dsmax.

I'm mostly curious if something is wrong with my workflow that needs to be corrected in order to avoid sharp highlights like this.

Thanks for all answers so far!
-t

[vladimir.nedev]

Try resetting the AA filter to the default to make sure you haven't chosen one that is making the edges jagged.

As mentioned before, the physically accurate way of fixing this is to enable bloom/glare.

The non-physical solution is to enable sub-pixel mapping (option hidden in the Channels viewport) and clamping in the Color mapping settings.
Doing this is not recommended.

Greetings,
Vladimir Nedev

[1funk]

If you look at his scene and render with the pixel info tool, this doesnt seem to be a problem due to values over 1.0 (they are only very slightly over if you do a zoom)

The shape of the geometry is just creating a very thin reflection which v-ray's default AA settings are not able to handle very well.

I have this issue with v-ray as well. I also use octane and modo and they deal with this problem much better.

Here is a screenshot of v-ray (top), octane (middle), modo preview (bottom). If anyone has a good solution to this problem, please let us know.

[1funk]

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