Wow, things have come a long way since I last looked. Kudos to HP and Alex and everyone else involved.
If you're wondering what the deal is with these different spaces (ACEScc, ACESproxy, and ACEScg) have a look under "ENCODINGS AND METRICS" here: http://www.oscars.org/science-technology/aces/aces-documentation Check it out even if you're not interested in the the math. Each one has a short plain-English introduction explaining the what and why for that space. On Tue, Jul 7, 2015 at 12:15 AM, Jose Fernandez de Castro < [email protected]> wrote: > ACEScg is definitely what you would want to use. Using the whole ACES > color space in Nuke causes a lot of issues, specially when going back to > more narrow color space. ACES 1.0 should include ACEScg, I think. > > On Mon, Jul 6, 2015 at 11:08 AM, Michael Garrett <[email protected]> > wrote: > >> Any comment on using ACEScg in Nuke, and why there is no Rec709 rrt? From >> reading the ACEScg white paper, it does seem there is just a matrix that >> can be used. Also I notice OCIO ColorSpace has ACES to rrt Rec709. >> >> On 6 July 2015 at 13:55, Deke Kincaid <[email protected]> wrote: >> >>> Just a note to add to Matt's post. Do not use the ACES or IIF included >>> with Nuke as it is 3 years old (ACES v0.1.1). Get the ACES 1.0 OCIO >>> profile off the Academy site (it links to HP's current fork of the OCIO >>> configs on github). >>> >>> >>> http://www.oscars.org/science-technology/sci-tech-projects/aces#field-tabbed-content-tab-1 >>> >>> That should be it. One possible hitch -- I think the EXR writer doesn't >>>> know that you're in ACES so won't write the metadata about ACES. (Anybody >>>> know if that's still the case?) >>> >>> >>> Nuke does not support writing the "chromaticities" metadata at the >>> moment and you can't simply use a modifyMetadata to add it as it's not a >>> simple string. Also we do not yet support the ACESClip sidecar file at >>> this moment either. >>> >>> -- >>> Deke Kincaid >>> Media & Entertainment OEM Development Manager >>> The Foundry >>> Skype: dekekincaid >>> Tel: (310) 399 4555 - Mobile: (310) 883 4313 >>> Web: www.thefoundry.co.uk >>> Email: [email protected] >>> >>> On Mon, Jul 6, 2015 at 1:27 AM, <[email protected]> wrote: >>> >>>> Hey Matt, >>>> >>>> I have to test some of those things and will get back to you. Or >>>> hopefully not. :) >>>> This is just a quick Thank You for your thorough explanation. >>>> >>>> Greets, >>>> Igor >>>> >>>> >>>> >>>> Am 05.07.2015 10:05, schrieb Matt Plec: >>>> >>>>> On Fri, Jul 3, 2015 at 10:04 PM, <[email protected]> wrote: >>>>> >>>>> Hey guys, >>>>>> >>>>>> I am trying to wrap my head around ACES. >>>>>> >>>>> >>>>> I'm sure you're not the only one. I have heard that before... Here's >>>>> the basic idea: >>>>> >>>>> First off, for anyone who hasn't thought much about color management >>>>> in general, why does it matter? >>>>> >>>>> When you work with color in the computer it's just numbers, so we need >>>>> a way to define what color, in some absolute way, [1.0, 0.0, 0.0] >>>>> means. >>>>> >>>>> What do you need to turn a [1.0, 0.0, 0.0] from Nuke into to see the >>>>> same color projected by a DCI compliant monitor as you see on your >>>>> workstation monitor? Or if you've got an sRGB JPEG and a REDcolor clip >>>>> does the value [1.0, 0.0, 0.0] mean the same color in the scene? (No!) >>>>> A colorspace specification like sRGB, rec709, AdobeRGB, and ACES >>>>> defines that. Which in turn makes it possible to transform color >>>>> values between one space and another. >>>>> >>>>> There are two key parts to a colorspace: the colorimetry -- the >>>>> primaries & white point that specify the hue/shade intended by a color >>>>> value -- and the transfer function (or encoding), which specifies how >>>>> the increase/decrease of values is encoded -- log, some gamma, etc. >>>>> >>>>> When you read an image into Nuke you might have noticed that the >>>>> (so-called) colorspace knob only defines the encoding. As a result, >>>>> there's sort of a built-in assumption that you are working in the same >>>>> colorimetry as your input images (and that they are all the same) and >>>>> all you need to specify is the transfer function to make them linear. >>>>> That was true (ish) when everything came from a film scanner and went >>>>> back out to a film printer. (err... well, let's not get into that.) >>>>> And we hack around it with Colorspace nodes. >>>>> >>>>> Luckily, by the nature of digital capture devices, their colorimetry >>>>> is known (even if only to the manufacturer) so a translation to well >>>>> known spaces can also be defined. Then as a practical matter we just >>>>> need to pick a working space to transform different sources into for >>>>> processing and back out of for display/delivery. >>>>> >>>>> In the past we knew what the "from" was based on file type, headers, >>>>> etc. (hopefully) but there was no well-defined standard "to" (though >>>>> it's essentially de facto been sRGB/rec709). >>>>> >>>>> Enter ACES. >>>>> >>>>> So, from what I understand ACES gives us on hand more gamut and on >>>>>> the other hand it is a way to bring footage together from different >>>>>> sources more easily. >>>>>> That sounds good, right?! Ok, but I never used that kind of >>>>>> workflow, and it does not seem to be that trivial. >>>>>> >>>>> >>>>> I think you'll be surprised. Conceptually it actually isn't really >>>>> much more than what happens now in Nuke. >>>>> >>>>> By default when you read an image in it goes through a process to >>>>> linearize it. When you write it out it goes through another process to >>>>> log or gamma it. If you're working in ACES that process just involves >>>>> more math to change the colorimetry in addition to the encoding. For >>>>> you as a user it's just more manual because of outdated assumptions >>>>> built into the Read/Write, and there are some gotchas to watch out >>>>> for. >>>>> >>>>> Since the Read & Write only do a 1D LUT for colorspace, you need to >>>>> use OCIO nodes to do the input and output colorspace transform >>>>> instead. Which means setting the Read/Write colorspace knobs to >>>>> linear. But if you do this and you're converting to/from log with >>>>> OCIOColorSpace or OCIOLogConvert then the Write can't autodetect that >>>>> you're writing log and set the dpx headers correctly, so you need to >>>>> set the transfer knob manually. >>>>> >>>>> In the Project Settings' OCIO tab, pick the ACES config and set the >>>>> viewer LUTs to use OCIO luts so you get the ACES conversion to >>>>> rec709/sRGB for display on screen. >>>>> >>>>> Congratulations, you're working in ACES. >>>>> >>>>> The scenario: >>>>>> I've got R3D files which I push through hiero to generate openEXRs. >>>>>> Problem I've got is I do not see an option to set the exrs for ACES, >>>>>> like in REDCINE where I can specify that in the export settings. Ok, >>>>>> comparing those two (redcine aces exr vs hiero exrs) the difference >>>>>> is visible, most prominent the reds seem more pushed or saturated in >>>>>> a non-aces exr. >>>>>> >>>>> >>>>> If you've selected ACES for your OCIO config, then your inputs are >>>>> converting to ACES on read and the colorimetry of the output EXRs will >>>>> be ACES since there's no conversion when writing to EXR. >>>>> >>>>> Now my questions: >>>>>> When I process them as aces, I also need a display LUT so that I see >>>>>> the right output, right? Is this provided with the OCIO Aces Config? >>>>>> Have to take a look at that. >>>>>> >>>>> >>>>> Yes. >>>>> >>>>> What do I do with CG content? Do I apply a LUT in Maya, or even to >>>>>> the render itself? Or do I treat it as usual and just transform the >>>>>> color into ACES space? To what do I render? ACES or nonACES plate? >>>>>> Do I treat CG simply as scene referred light? >>>>>> >>>>> >>>>> You'll need to convert your textures from whatever space they're in >>>>> now to ACES, either by converting the files or setting something on >>>>> your texture reads, like you'd do to linearize them. I don't know >>>>> about others, but MODO supports OCIO so you can pick the ACES config >>>>> and then just make sure your texture inputs have the right colorspace >>>>> set. And of course view through the ACES sRGB or rec709 LUT so the >>>>> image gets translated properly for your display. Essentially the same >>>>> as in Nuke. >>>>> >>>>> How do I export in Nuke exrs in aces? Simply set to linear and >>>>>> everything is fine, or more magic sauce? >>>>>> >>>>> >>>>> That should be it. One possible hitch -- I think the EXR writer >>>>> doesn't know that you're in ACES so won't write the metadata about >>>>> ACES. (Anybody know if that's still the case?) The files are EXRs just >>>>> fine of course but anyone else relying on that metadata to identify >>>>> them as ACES won't find it. Maybe someone's got a ModifyMetadata node >>>>> they could share that puts the right stuff in, to chain in before the >>>>> Write? >>>>> >>>>> Hope this helped! >>>>> >>>>> I am a bit confused, and any (non-technical as possible) >>>>>> explanation, tip, link, whatever is highly appreciated. >>>>>> >>>>>> Thanks in advance, >>>>>> Igor >>>>>> _______________________________________________ >>>>>> Nuke-users mailing list >>>>>> [email protected], http://forums.thefoundry.co.uk/ >>>>>> [1] >>>>>> http://support.thefoundry.co.uk/cgi-bin/mailman/listinfo/nuke-users >>>>>> [2] >>>>>> >>>>> >>>>> >>>>> >>>>> Links: >>>>> ------ >>>>> [1] http://forums.thefoundry.co.uk/ >>>>> [2] >>>>> http://support.thefoundry.co.uk/cgi-bin/mailman/listinfo/nuke-users >>>>> >>>>> _______________________________________________ >>>>> Nuke-users mailing list >>>>> [email protected], http://forums.thefoundry.co.uk/ >>>>> http://support.thefoundry.co.uk/cgi-bin/mailman/listinfo/nuke-users >>>>> >>>> >>>> _______________________________________________ >>>> Nuke-users mailing list >>>> [email protected], http://forums.thefoundry.co.uk/ >>>> http://support.thefoundry.co.uk/cgi-bin/mailman/listinfo/nuke-users >>>> >>> >>> >>> _______________________________________________ >>> Nuke-users mailing list >>> [email protected], http://forums.thefoundry.co.uk/ >>> http://support.thefoundry.co.uk/cgi-bin/mailman/listinfo/nuke-users >>> >> >> >> _______________________________________________ >> Nuke-users mailing list >> [email protected], http://forums.thefoundry.co.uk/ >> http://support.thefoundry.co.uk/cgi-bin/mailman/listinfo/nuke-users >> > > > > -- > Jose Fernandez de Castro > > _______________________________________________ > Nuke-users mailing list > [email protected], http://forums.thefoundry.co.uk/ > http://support.thefoundry.co.uk/cgi-bin/mailman/listinfo/nuke-users >
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