Preset model

A preset is a description of an edit. This page explains the design decisions behind that description: why presets describe what they change rather than the full parameter set, and the patch-on-baseline mental model that follows from that choice.

If you want to look up how extends resolution works mechanically, see the preset model reference.

Why partial parameters

Most edits change only a handful of knobs. A film-emulation preset might set saturation, white balance, a tone curve, and a LUT — leaving everything else at default. Modeling parameters as partial (every field is optional) means the preset only describes what it changes, and a reader can see the intent at a glance.

This also makes presets composable: a base "neutral starting point" preset can be extended by a "warm cinematic" preset that only specifies the warmth and cinematic-curve overrides.

Mental model

Think of a preset as a patch applied to a baseline render, not as a complete description of an edit. The baseline is "engine defaults applied to the input image." Each preset in the extends chain stacks its overrides on the baseline. The final rendered image is the result of applying every override in chain order.

This mental model is why extends is useful: it reflects how editing actually works — small adjustments layered on top of larger style choices, each of which builds on a more general starting point.

See also