ACES in Production
Colorspaces are easy now, right?
Restructure note: this guide is the workflow flagship, rebuilt from the current
understanding-color-spacespage. It keeps everything about moving color between spaces and all encoding / transfer-function content. The “what color is” material (cones, metamerism, gamut) moves out to What is a color anyway? and is linked, not repeated. Centerpiece is the working-space chooser.
ACES isn’t complicated. It’s just unforgiving about which space you’re in at which step.
[Cold open. Lead with the failure that ACES prevents, then promise the payoff: by the end you can name the right space for any step and say why. Optionally reuse the “five renders, four wrong” hero from the current guide.]
Transfer functions
[Linear vs log/gamma, and why they exist — one-paragraph callback to the perception point from “What is a color anyway?”, then move on. This guide owns the encoding story end to end.]
A transfer function is the only thing standing between linear light and the numbers you store.
The bit budget
[“8-bit hell.” Where banding hides, why the shadows pay first, and why grading happens in float. Keep it concrete and short.]
The same 8-bit gradient encoded linear vs perceptual; watch posterization bloom in the shadows. Most extractable widget if this guide gets unwieldy — can drop to an inline interaction.
Hub and spoke
[ACES as architecture: IDT → working space → ODT. The hub-and-spoke mental model that makes the rest of the guide make sense.]
Everything enters through an IDT and leaves through an ODT. Miss either and the image lies to you.
Interactive diagram. Drag a source in through an IDT → working space → out through an ODT. Pick the wrong IDT or skip the ODT and watch the image break.
Which working space when
[The spine of the whole guide. ACEScg (linear-light, for compositing and lighting math) vs ACEScct (log-shaped, for grading) vs ACES2065-1 (archival / interchange). This is the part interns most often get wrong. The aha: these aren’t interchangeable preferences — each is shaped for a specific operation.]
ACEScg for the math, ACEScct for the grade, ACES2065-1 for the archive.
The teaching version, not a lookup. Pick a task (rendering, grading, archival, interchange); the widget shows which space and why. Toggle ACEScg vs ACEScct on the same grade operation and see why cct’s log-ish curve makes grading controls behave while cg’s linearity is right for compositing math.
Reading scopes
[Waveform and vectorscope as the daily diagnostic for “what colorspace am I actually in.” The skill that pays off forever.]
Live waveform / vectorscope reading a sample image. Flip the interpretation tag (sRGB vs Rec.709 vs raw log) and watch the trace lie vs snap correct.
Picking the right space
[Closer. The “how to pick the right colorspace” decision tree, which mostly falls out of the working-space chooser. Possibly reuse the reference card / glossary from the current guide.]
[Closer line. To be written.]
Glossary
Every term used in this guide, defined once. In the prose, underlined-dotted terms show their short definition on hover or focus, and jump here on click.
- Transfer function
- The curve that converts linear scene values to encoded values and back. Linear keeps values proportional to light; log/gamma spends bits where the eye looks.
- ACEScg
- Scene-linear, wide-gamut working space. The right space for rendering and compositing, because light math only behaves when values are linear.
- ACEScct
- A log-shaped encoding for grading. Its curve makes grading controls feel even across the tonal range — the reason colorists work here, not in ACEScg.
- ACES2065-1
- The interchange and archival space, spanning the whole visible spectrum (and beyond). For handoff and storage, not daily work.
- IDT
- The transform that brings raw camera or asset data into ACES working space. The first spoke of the hub.
- ODT
- The transform that shapes ACES working color for a specific display. A creative compression by design — not reversible.
- Banding
- Visible jumps in what should be a smooth gradient. A bit-depth / quantization symptom that shows up first in the shadows.