Jump to content

ACES is an absolute Gamechanger


DasFrodo

Recommended Posts

19 hours ago, CDALive said:

 actualy it is simple, ACES is just the  System. a kind of an universal converter. So you can bring every color space from every camera into that system and the color grading is the same dosn't matter what input you bring in.  ACES the System is only in Postproduction. Renderings is ACEScg or ACEScc. So it is a great system for 3D and VFX stuff.

 

In the Filmproduction you film with different Cameras and the output is HD, SHD or UHD so the Color space of that cameras is very big . So ACES is not a must go in the Movie production.

 

for CG it is a game changer for sure.

That is not entirely true. The original idea for ACES came from a digital Hollywood production frustration:

 

You had for example 3 different camera manufacturer systems on set and like 4 different VFX facilities and two editing facilities in your 100 million dollar movie production. So in the first step you received the plates from the 3 cameras which all looked different because every one has a custom color system. So first you needed a color grader to unifiy them.

 

Now you give them out to VFX for effects. Every VFX studio had a custom color workflow in the 90s so when you got the film with vfx back it looked different again. So the next round of 3 days of color grading started to unify the look. Now give it to editing. The same started. Now the director wants 80 takes to be changed. And it starts all over again. It was eating a lot of time and money and frustration.

So they said: we need a technical system that covers all existing color systems and merges them into one: ACES

 

So ACES is not really only CG orientated. It wants to merge all the multiple color systems and avoid all the annoying conversions between them to create the best possible standard for the digital image space. It took them 10 years and is still  not finished. See here. ACES is so "big" and advanced it covers all the others "inside" its range to not destroy the image:

 

https://learn.foundry.com/mari/4.2/Content/Resources/images/user_guide/color_management_4_453x477.png

 

It is way more powerful than those spaces we use everyday like sRGB and Rec709 in digital image creation. Problem is: our TVs and Screen are still in SRG/Rec709/Rec2020 so when working in ACES we need to "shrink" our footage back into the space of the output device.

Link to comment
  • Guest featured this topic
  • Customer
3 hours ago, Igor said:

Here is a blog about everything you need to know about ACES. 

 

Chapter 1.5: Academy Color Encoding System (ACES) - Chris Brejon

 

And nice useful app to convert your HDRIs and textures.

PYCO Image Colorspace Converter [Free] (gumroad.com)

 

Awesome Igor! That conversion tool is great

Link to comment

015_ACES_0040_aces_colorspaces_FHD.thumb.jpg.2a27a8f886af5d78f6d54925a883c2d0.jpg015_ACES_0040_aces_colorspaces_FHD.thumb.jpg.2a27a8f886af5d78f6d54925a883c2d0.jpg

On 4/11/2021 at 10:00 AM, zeden said:

So ACES is not really only CG orientated. It wants to merge all the multiple color systems and avoid all the annoying conversions between them to create the best possible standard for the digital image space. It took them 10 years and is still  not finished. See here. ACES is so "big" and advanced it covers all the others "inside" its range to not destroy the image:

 

https://learn.foundry.com/mari/4.2/Content/Resources/images/user_guide/color_management_4_453x477.png

 

It is way more powerful than those spaces we use everyday like sRGB and Rec709 in digital image creation. Problem is: our TVs and Screen are still in SRG/Rec709/Rec2020 so when working in ACES we need to "shrink" our footage back into the space of the output device.

 

Although the above chromaticity diagram commonly gets thrown around to represent ACES (i.e., as ACES2065-1), we are instructed to not use that color space for rendering, but to instead to use the much smaller ACEScg color space (see the two compared in the first diagram, below) which represents a much smaller color gamut that is closest to Rec. 2020 (see subsequent diagram). We still lose out on a good chunk of the greens, cyans, and blues, as with Rec. 2020. For now, there aren't any devices that can display these colors anyways, but 10-20+ years down the road... Who knows?

 

Diagram comparing ACES2061-1 and ACEScg on the two common chromaticity diagrams

015_ACES_0040_aces_colorspaces_FHD.thumb.jpg.2a27a8f886af5d78f6d54925a883c2d0.jpg

 

Diagram comparing ACES2065-1 and ACEScg with other common color gamuts

Gamuts_Plot.thumb.jpg.13a12f663cbde8169a3ad4fedf4bd41a.jpg

Link to comment
  • Guest unfeatured this topic
  • 3 months later...

Finally - just this week - I got some space and time and did it...
I've spent a week learning, testing and developing - and have now completely revised my workflow to an ACES based one - from rendering through compositing. It's not been easy, but I think it will be worth it. 

 

I've just completed the first job on the new workflow and it's gone well. Unfortunately it's under strict NDA, so I can't share the images. Hopefully I might have some I can share in the future.

 

If you want to get better output and much more post-render compositing  flexibility I'd certainly give it some serious thought. 

Link to comment

I prefer filmic: ACES has glaring issues. I am not an expert, but after reading up on it (specifically hearing Troy S talk about Filmic, ACES, etc. in a live talk that I attended a few years ago), I avoid ACES.

 

Troy S (who is and expert on colour management and colour spaces. etc) had this to say about ACES in a nutshell:

 

Quote

This is digital RGB lowest-common-denominator garbage. Think sRGB Mark II.

Quote

ACES generates garbage imagery by default.

Feel free to dive into it and actually pay attention to what the working space values are and the hideous posterization, gamut clipping / hue skewing.

There’s a very good reason that a massive colourist shop and plenty of cinematographers avoid it like the plague. It’s dead in the water on that front.

Quote

The bottom line is that all displays are limited. They have three specific lights they can project out of, and a range of emissions of those lights. ACES simply does a brute force 3x3 and a transfer function, and all values are clipped to the displays gamut.

This means flesh tones turn rat piss yellow, skies skew to cyan, and the typical digital RGB gaudy looking broken / skewed colours abound.

 

Too much to go into now, but if you are interested in this (admittedly involved and huge) topic, and wish to become more informed about whether or not to use ACES in your workflow: read up on it via the sources below.

 

The way to go forward is Spectral rendering, in my opinion. Octane already supports this. A special Blender build also exists with Cycles enabled for spectral rendering:

https://blender.community/c/graphicall/Cnbbbc/?sorting=hot

 

Does Redshift support spectral rendering? I should check.

 

Sources:

https://devtalk.blender.org/t/blender-support-for-aces-academy-color-encoding-system/13972/105

https://blenderartists.org/t/installed-aces-color-management-to-blender-now-im-confused/1236883/16

https://docs.google.com/presentation/d/1kk9jx5qK4E2cbHq_0IOujDELmb3rC6-HErszMQDi5rA/edit#slide=id.gc6f73a04f_0_14

https://jo.dreggn.org/home/2021_spectral_imaging.pdf

 

Link to comment

I understand the issues, albeit at a modest level  -  hue skewing etc. Is it perfect? No of course not. When you are trying to squeeze the range of natural light and colour into a representation on a limited display it's going to get squashed one way or the other. I've looked at Filmic as well and felt that ACES was the better match for me and my work. I'll see how it goes over the next year or so. Everyone to their own : )

Link to comment
7 hours ago, hvanderwegen said:

I prefer filmic: ACES has glaring issues. I am not an expert, but after reading up on it (specifically hearing Troy S talk about Filmic, ACES, etc. in a live talk that I attended a few years ago), I avoid ACES.

 

Troy S (who is and expert on colour management and colour spaces. etc) had this to say about ACES in a nutshell:

 

 

Too much to go into now, but if you are interested in this (admittedly involved and huge) topic, and wish to become more informed about whether or not to use ACES in your workflow: read up on it via the sources below.

 

The way to go forward is Spectral rendering, in my opinion. Octane already supports this. A special Blender build also exists with Cycles enabled for spectral rendering:

https://blender.community/c/graphicall/Cnbbbc/?sorting=hot

 

Does Redshift support spectral rendering? I should check.

 

Sources:

https://devtalk.blender.org/t/blender-support-for-aces-academy-color-encoding-system/13972/105

https://blenderartists.org/t/installed-aces-color-management-to-blender-now-im-confused/1236883/16

https://docs.google.com/presentation/d/1kk9jx5qK4E2cbHq_0IOujDELmb3rC6-HErszMQDi5rA/edit#slide=id.gc6f73a04f_0_14

https://jo.dreggn.org/home/2021_spectral_imaging.pdf

 

 

I'm sorry but I have a hard time believing this, and the very colorful wording in the quotes doesn't help.

 

I think there's a reason why CGI has started to look better ever since ACES was introduced. There's tons anecdotal info on why for example the LEGO movie looked as good as it did and most of that is attributed to ACES (aside from very talented artists of course). I have tried it myself and it just looks better, in my opinion. Sure, maybe you can produce the same effect via linear workflow and lot's of grading, but I prefer the output ACES delivers because it's faster. I haven't dabbled in gradin with ACES yet, though.

Visit my Portfolio on Artstation.com & Follow me on Instagram

Link to comment

One of the most important things to understand IMO with this higher dynamic range rendering - whether filmic, ACES or whatever - is that correct PBR based materials and lighting are key components as well. Not enough emphasis is given to that.

 

'White' needs to have a diffuse value of around 80% for typical surfaces. With that you'll be able to pump up your lighting to more realistic 'sunlight' levels - and therefore get better GI and overall more realistic light interaction. Eg: One dome light, one box with a realistic window sized hole... straight out of the renderer:

 

BIAB_01.jpg.6a3466daf3fb333d9fb76a7eda0d575d.jpg

 


I can certainly remember the days when we couldn't even imagine getting a result straight out of the renderer like this. So, whether you choose to use Blender + filmic, or ACES, or whatever - rejoice and be happy : )

 

 

 

 

 

Link to comment
×
×
  • Create New...

Copyright Core 4D © 2023 Powered by Invision Community