AA with Lights and reflections

Hi there,

I have some problems with over bright area in my images.
Here is a image so you can see the problem.

I already had that with direct visible lights and with reflection of lights in some other materials like steal.

Does some-one know what I have to do to avoid it ?

I already tried with a lot of different AA filters, but they seems to have all that kind of problem.

Thanks for your help.

Stan
3LP Team

that is to be expected with pixels which values are way beyond 1.0, as I guess those lights are. you can try checking sub pixel mapping, and clamp output in the colour mapping rollout.

yes i will try that now, say you what soon.

but it’s normal to use high multiplier with those lights when I use VrayPhysicalCam, no? I have to put lights @ 90 or something like that to have a iso @ 100 and a shutter speed @ 1/50.

Am I all way wrong to light all my scenes ?

Yes !

it’s the sub-pixel mapping !

you’re great ! thanks a lot.

btw, what does it do actually the sub pixel mapping, why isn’t it always on ?

It used to always be on, but with it off, you get a more correct brightness. From the vray online help:

Sub-pixel mapping - this option controls whether color mapping will be applied to the final image pixels, or to the individual sub-pixel samples. In older versions of V-Ray, this option was always assumed to be on, however its default value is now off as this produces more correct renderings, especially if you use the universal settings approach.

Just to make things clear, it’s not really the sub-pixel mapping (though it will help a little, or more) but the unclamped values the aa needs to deal with. Sadly, this is not a bug, rather a feature. I wonder how other engines battle with this issue. Oh, and of course, turning on clamp output is not advised at all if you plan to keep the hdr data of your render. :smile:

Nice space by the way! Just make sure those pillars meet up with the beams. :wink:

Best regards,
A.

as aldaryn says, what happens there, is basically vray has to do the aa with pixels brighter than 1. which will result in solid white pixels, even when those pixels are antialiased, and jagged lines.