exporting LUT out of VFB and using in Nuke, in ACES?

[emartin8907]

I'm trying to export out my Filmic Tonemapping from the VFB and apply it in Nuke, is this possible?
I exported out of VFB a .cube LUT and in nuke am trying to apply it with a vectorfield node, but it looks WAY too bright, tried every combo of input/output colorspace settings and it all looked wrong, I believe they should both be set to linear.

I am using ACES workflow, and am wondering if this complicates what I am trying to do? Can anyone help has anyone done this?

[hermit.crab]

Okay, we figured out what's going on. It seems the Display Correction (except None and sRGB) is baked into the LUT when exporting from the VFB. To get identical results, you just need to set the Display Correction to None and then export the LUT. No need for the above hassle this way.

EDIT: Logged an issue (internal tracker id: VFB-146) to improve this behavior.

[hermit.crab]

Try adding an OCIODisplay node before applying the LUT, where input space/display device/view transform matches the one in the VFB, and check "invert direction" (note it works on 32-bit images only).

[emartin8907]

thanks, gave your suggestion a try but no dice, came out looking mega burned and off in nuke.

[hermit.crab]

How about if below the LUT, you add an OCIOColorSpace (input: sRGB, output: ACEScg)? I think the issue is that there's an additional sRGB curve applied within the exported (from the VFB) .cube file.

[hermit.crab]

Okay, we figured out what's going on. It seems the Display Correction (except None and sRGB) is baked into the LUT when exporting from the VFB. To get identical results, you just need to set the Display Correction to None and then export the LUT. No need for the above hassle this way.

EDIT: Logged an issue (internal tracker id: VFB-146) to improve this behavior.

[emartin8907]

NICE that worked, ahh thank you so much!! this is great!!!

[piotrus3333]

if nothing changed very recently - VFB is not able to export Filmic tonemapping (or any other tonemapping) to a lut.
Created and applied LUT in VFB looks different - Chaos Forums

[hermit.crab]

if nothing changed very recently - VFB is not able to export Filmic tonemapping (or any other tonemapping) to a lut.
Created and applied LUT in VFB looks different - Chaos Forums

No changes based on a quick look at the changelog. I presume that thread was dealing with the issue discussed here. Try it out if you wish.