Dealing with Aces , AGX, Srgb

There are things like procedural materials you know? Where you can pick the tint of the material…

What’s up with using procedural materials? Who does that? Where does everybody get procedural materials from? What is this workflow? What do you use it for?

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To create images

I think thorn was facetious on that one

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This would be a valid argument, if there was a solution for that. But what is the solution? Different contexts use different color management. There is no adequate default. One should use whatever the system they create assets for uses. …or accept it’s going to look different. If you were to accept it’s going to look different, it is still good enough, because you can actually see the detail, the colors don’t blend together in the highlights. It’s the same as when you are creating a PBR asset in neutral lighting, you cannot know, how it’s going to look in the actual scenes it’s going to be used in. If we are talking about PBR, we can forget about all the arguments about the user not being aware of what they are doing as well. Standard sRGB transform is also no good at all for that. Should filmic be the default? It will not be perfect for this either. ACES?.. What is good for it?

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Images are just a figment of perception; we don’t truly “see” an image. Our mind merely interprets the neurons, and compares it to things we’ve seen before… or imagined. This is why color management is so difficult, because you cannot manage that which doesn’t exist. Everyone’s imagination is different, therefore there’s no such thing as color or light… we cannot actually see the difference between burned toast and fresh bread, only taste it…

So in essence, you can use whatever color you like… unless you’re hoping to recreate this dress in Blender, in which case you should use AGX. Or not.

The ones I am dealing with pretty much preserve the hue, except for one…

You can make it more intuitive if that is the goal…

I’m quite sure that you could beat any record of posts for a single thread. :slight_smile:
Colors, natural or artificial doesn’t actually matters, are one of the most subjective argument you could debate on.

About Agx in Blender, as my main field is archviz, I’m quite happy about the highlights management. It’s possible to raise exposition without burning everything. And it’s a plus from my point of view.
As Blender still give us the opportunity to stay with sRGB or Filmic (I’ve never loved too much), I think that has more value the freedom to choose from than “have one color transform for all / everything”.
Obviously, if there is space for improvements, they are welcome…but I’m not a color transform technician so it’s quite difficult to judge the work donw until now.

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Which makes it clear that it was not necessary to put gamma correcting into the color picker! Gamma correction should come later, the color picker should work the same as across the bulk of the CG industries (IMHO).

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NO!

Blender is a program running on a computer, a digital machine. Unlike our eyes and brains, which are analog machines, Blender works with numbers. Even though the intent (for realistic artists) is to create visual effects that strongly resembles what we see with our eyes, or with an analog camera for photorealism, everything that happens to get each phosphor on your LCD screen to glow a specific way is numbers. That glow is analog, the photons emitting from it into the air are analog :asterisk:, the eyes those photons (plus all the ambient photons, like those bouncing off of red curtains) hit are analog, the brains connected to those eyes are analog.

Despite the profoundly analog/cognitive/subjective whishy-washy timey-whimey nature of what happens once the photons emit from your computer screen? Even though visual artists end (or near-end) goal is to create analog effects, the art tools we’re using here are digital – we demean, dismiss, disparage, etc that at our peril. What the Blender devs are doing is making (among other things, but this is about color) tools to get specific phosphors on the screen to produce specific glows. Anybody arguing about how important human cognition is to color perception (and it is, granted) or any of the analog stuff are (IMHO) profoundly off-topic here.

Like all computer programs, Blender works with objective data. Hue, Saturation, Value, etc are terms that have specific objective meanings in computer graphics, can be objectively measured, can be objectively communicated. If “hue” had a different meaning in your painting class? (Yeah, mine too.) Okay, but what we’re talking about in this topic is computer graphics, when somebody says “Hue” here the default is the computer graphics definition. And because there were out-of-ambit definitions being used, it seemed to me that some clarification (with visual aids from the UIs of a few CG FOSS’s) would be useful to the discussion.

If Blender’s AgX has hue-shifting, that can be objectively measured. Arguments about what happens after the photons leave the computer screen does not change that. If it’s caused by code over-compensating for something, that should be fixable in the code. Computer Graphics coding has been working on these issues since at least the Cornell Box, there’s a significant body of work to draw from (no pun intended).

Getting back to “should AgX be Blender’s default View Transform?” Better than Filmic doesn’t mean it’s ready for prime time, IMHO. I liked Joseph’s take, acknowledgement that there is no valid default and the setup questions should ask what kind of art the user is going for might be a good idea. But if there has to be a default, I think something that’s more widely used/understood across the CG industries as a whole, instead of privileging realism artists, is the way to go – Standard is standard, yes?

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:asterisk: Lets not get into particles vs waves here, they’re part of the analog realm and are therefor analog in a practical sense.

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I don’t think it’s about defaults here at all. If you want to create good assets for scene referred workflow, you have to be used to what the view transform does and know what to expect. You are working with values in your scene, not with values that you see directly on screen. So it doesn’t matter what it is that much, just that you know what to expect. You can probably get used to anything. It’s probably harder to get used to standard sRGB transform, because you will not see most of the stuff you are working with at once, but I think you could even choose that masochistic path if you want to… i don’t think you can base this on logic much, it seems to me in this case it’s going to be simply personal preference what to work with if it’s impossible to use whatever the end result will be used in. It’s going to look different in different contexts anyway.

So knowledge here is the solution, not some default.

Painter actually seems to support OCIO as well, so in theory, yes one could maybe match it all based on AgX. But then I don’t have a HDR monitor, so that could maybe make things a bit more confusing.
So at this stage I think I’m happy to just stick with my Standard setup across all 3 that pretty well match and render to OpenEXR if I want or need to mess around with the final colour in DaVinci Resolve.
It’s not like I’m doing anything that needs to match or work with various film/camera output, so right or wrong at this stage really doesn’t worry me, I just want it to look how I want it to look.

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It also features a color picker, as I recall. Quite a useful tool at times, that.

lol what does digital vs. analog have to do with anything here. That’s just about how numbers are represented “under the hood”. Either style of computing can be used to the same effect. People have built analog computers in the past.
And you could easily argue that the brain is digital as well, namely, individual neurons either fire or don’t fire.

So… how are you judging whether you are looking at “the same red”… without, you know, perceiving said instances of red?

Should note that RGB values don’t actually represent a color per se. They represent how strongly you activate a particular, arbitrarily picked set of three different light sources, with an overall scaling applied to achieve a particular white point. And the hue you calculate is based on the particular RGB you choose.
So no, it’s not really an “objective” thing, even in math terms, as there are infinitely many such choices for light sources (along with the white point), and each of them are going to give you different corresponding hues.

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Not required. You just keep adjusting the stops as part of the painting process!
And notably, AgX is going to compress your HDR range to SDR anyways. That’s like half its point.

But yes, it’s certainly a completely different kind of workflow.
It’s pretty fun though. I’m not saying you should absolutely definitely switch over. There is a use case for everything. But you should certainly at least give it a try at some point :smiley:

The workflow is generally pretty much like:

Use layers in Add mode to add light, use layers in Multiply mode to emulate bounce light of a certain color

Yes it does, and just like Blenders now new 4.0 picker, it lets you click on anything, even outside of the painter window, to sample the colour. Very handy when one has created character colour keys in Krita as what the overall general base colour should be, before lights, shadows, roughness, highlights, bump/normal etc all get applied.

You should have stopped. Even this most basic thing… It’s wrong. Computer screens emit only Red, Green and Blue light only. They don’t emit yellow, they don’t emit orange, they don’t emit pink. Pink actually doesn’t even exist. :smiley: There is no light wavelength for pink… anyway… It’s not that simple.

This is a terrible way to phrase it imo.

Pink “doesn’t exist” in the exact same way almost all colors we can perceive don’t “exist”. Namely, it requires a mixture of at least two wavelengths to display.

Well guess what, aside of the literal colors of the rainbow (as seen in actual rainbows or CDs or similar), that’s true for ALL colors we can perceive!

(that’s before various perceptual filters come into play, so actually there’s a ton of extra caveats here)

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Yes, of course it’s wrong – I was attempting to communicate it using words.

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Words are just an abstract… unless one uses a word picker.

(Yes, I know the joke doesn’t contribute to a serious conversation… but this entire conversation started bordering on absurd in the past 2-3 days, so I might as well go with the flow.)

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Indeed. Much like pink, words don’t exist either- they’re entirely figments of human imagination that we’ve collectively assigned meaning. Talking about something that doesn’t exist using things that don’t exist is peak irony- it’s unfortunate we can’t communicate as a species by blasting each other with direct photonic beams of pure wavelengths.

(This is sarcasm, if it’s not obvious)

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