black pixel around lights

[themaxxer]

this is really bothering me for a long time now... I render without "sub pixel mapping" and "color clamp", it's also recommended (for vray next) in the help, but then all lights has these black pixels around the edge, because the withe pixels are so over bright. of course you can blend them with a high vray lens effect, but your light appears much bigger then, because you have to use a mutiplier about 5 or 10.

so watching on the corona site, there are no such problems... why in vray? is this fixable?

I would really appreciate a solution for this soon. I hope every time when an update is released to get a fix for this issue, but...

all the best and stay healthy.

best regards
themaxxer

[Buck]

what AA filter are you using? If it's a sharpening one (like Catmull-Rom or Mitchell-Netravali), that might be (part of?) the problem.

[themaxxer]

no, "vray lancos" the vray default one...

[^Lele^]

A scene to support would help figuring it out.

[themaxxer]

well, it's in every scene... here an image: https://c2n.me/477HzT7.png
but here I applied some lenseffects to hide the black pixels

[glorybound]

I have that as well with bloom/glare.

[themaxxer]

yes, but it's more visible without bloom/glare... I applied glare to hide it, somewhat.

[^Lele^]

I have to ask: do you have a LUT applied?
What you see smells awfully as negative colours, which can happen either because of a negative-component filter (As Buck suggested) or because some LUT is playing havoc with pixels outside of its valid range.
I can tell you i have absolutely no issue with hyperbrights, and besides those two cases, i can't think of any other part of V-Ray coming into play to produce those (i.e. we are wholly linear, and unclamped -in output-, by default.).
The request for a scene to support remains current.

Below, a light with default multiplier of 30, over a plane with a gray diffuse.

[themaxxer]

^Lele^ hm, you are right. I have to admit that I always used the VraySinc filter, but I don't wanted to... In a fresh scene with everything default I have no artifacts, but when I switch to VraySinc then I get them... I have to test now if LUT's also tend to artifacts as suggested from you. thank you for sorting out. I have learned a lot and I have to think about my workflows...
so, would it be better to not use any filters? it's a bit sad ther's no info about the Vray filters in the help, maybe this would help a lot of people to learn more about those implementations.

best regards
themaxxer

[^Lele^]

No problem, glad it's sorted!
By all means, filter your renders.
The choice is varied, but keep in mind that many of the currently available choices are there for compatibility, rather than preference.
The preferred filter type, VRayLanczos, has been modified to retain its sharp qualities, but not have a negative component, thereby not producing artifacts.
Notice that at default, it's as sharp as a box 1, or no filtering at all (i.e. it'd be hard to tell the difference in a normal image, you'd maybe able to tell on moire' patterns and the like), but will still do a better job than those in animations.
The help page is somewhat outdated (in that it doesn't cover all filter types.), but the info contained is still valid.

[kosso_olli]

no, "vray lancos" the vray default one...

So this was a lie then, right?