Highlight burn alters MMRE colors

[kosso_olli]

I have a big problem here. Using the Highlight Burn slider in the VFB also alters the colors for the MMRE. This doesn't make any sense to me, why would anyone want such a behaviour?
It doesn't have any effect on normals for example, but for MMRE this is very bad. Can this please be fixed in the future?

Max 2017, V-Ray 3.60.03

[svetlozar.draganov]

This doesn't make sense at all, I'll add a note about that into the system and will keep you posted once fixed.

[svetlozar.draganov]

This was actually reported long time ago but not yet fixed, here is a similar report 2 years ago.
https://forums.chaosgroup.com/forum/...ce-correction=

[kosso_olli]

It will be super helpfull if this could be fixed for the next update.

[svetlozar.draganov]

It's already with the highest priority and discussed as important feature, hopefully will wrap it up for the next release.
Until then you may consider always exporting V-Ray Raw Image File since it doesn't store Color Corrections so you will have unmodified version of MM element as well.

[kosso_olli]

Just noticed that White Balance also alters the MMRE colors. Can we make sure that none of the color corrections in the VFB affect the MMRE? Not even exposure?

[svetlozar.draganov]

Yes, lots of color corrections affects MultiMattes we know that. We'll fix everything not just the Exposure.

[piotrus3333]

probably the most ridiculous bug/feature(?) in vray. I even stopped waiting for it to be adressed - if some day that will be fixed (vray 4.0 most likely becouse of vfb redesign) it will actually break my in-office workflow a bit..

[svetlozar.draganov]

Yeah, I agree that this is a ridiculous bug which has been waiting too long for fix.
Maybe we didn't get much push for it cause most people that relay on MultiMattes don't export VFB color corrections. There is also a workaround which I don't claim its best possible solution but its pretty easy afterall.
How often do you guys are exporting images with VFB color corrections and then using MultiMattes?
Is it very difficult to work with color corrected matte elements?
Have you tried to export vfb corrections as a lut file and to load it in the image editor instead of baking the corrections into the image?
What about using other mask elements instead or in combination with multimatte one?

[kosso_olli]

I often do it, to be honest. Most of the time I do slight exposure corrections or I am using the contrast feature in the VFB.
Working with messed up MMREs is quite difficult. The masks don't have the right opacity in Photoshop afterwards, which always results in some faint transparency when making corrections in PS.
MMREs are the fastest way for us to generate pixel perfect masks for our kind of jobs.

[viscorbel]

I often use vfb color corrections and mmre as well. It's always an annoying problem - the mattes need some work to make them usable and it's a few extra steps in photoshop for every mask, as well as slightly degraded quality.
Can't wait until it's fixed.

[jackieteh]

what is MMRE ? sorry about my stupid question

[kosso_olli]

what is MMRE ? sorry about my stupid question

See here: https://docs.chaosgroup.com/display/...tiMatteElement

[anthonyh]

Mmm, useful. I usually just create my own matte passes but you get a lot of sequences. I shall investigate. Is this new to 3.5/6 ? I`m still stuck on 3.4 because of some problems I had with the latest. (I could probably upgrade and use workarounds, I just don`t want to have to find/remember different methods to do what I can do now without the extra work.)
anthonyh

[kosso_olli]

I'm surprised that this seems to be new to so many users. This stuff has been around since at least ten years. In my opinion this is still the best way to get a pixel perfect mask. I hate the multicolor masks like render ID and so on.