The Image Stack is the processing pipeline visible in Develop mode. It appears as a list of layers under the Editing Layers header in the edit panel on the right side of the window.

Layers

Input Layer

The first layer in the stack. Its title shows the decode engine in use:

  • RAW: Apple — RAW decoded by Apple’s engine.
  • RAW: Aphera — RAW decoded by Aphera’s engine.
  • JPG Image — display-domain images (JPEG and similar).

The Input menu on the row switches the engine for RAW files. Input settings may include lens corrections, DNG corrections, denoise, highlight recovery, and color matrix options.

Balance Layer

The seven tonal controls: Exposure, Temperature, Tint, Contrast, Shadows, Highlights, and Saturation. See Balance.

Formation Layer

A color transformation layer, labeled Formation with its type:

  • Formation: Aphera 2499 — Aphera’s image formation.
  • Formation: Custom LUT — a user-supplied LUT.

Formations apply on RAW images only. When a look carrying a formation is applied to a JPG, the row shows a warning and the formation is inert; the rest of the look’s layers still render. Modifying a look on a JPG drops the formation.

Effect Nodes

Stackable image effects added to the pipeline from the Add Layer menu at the bottom of the stack. The menu groups effects under Color and Texture:

Color

  • Grading
  • Color Controls
  • Film Response
  • White Balance

Texture

  • Diffusion
  • Grain
  • Halation
  • Sharpen
  • Vignette

Each effect node can be individually enabled or disabled.

Applied Look Layer

When a look is applied, its layers appear under a Look: name row. Hover or expand the row to reveal a Modify button, which unpacks the look’s layers into the stack for editing.

Save Look

The Editing Layers header carries a Save Look menu. It has two actions:

  • Create a new look — saves the current stack as a new look in the project.
  • Update “name” — overwrites the look the photo currently references. Shown only when a look is applied.

Both actions are available when the stack contains layers.

Expanding and Collapsing

Each layer can be expanded to reveal its controls, or collapsed to save space. The header of the edit list provides expand-all and collapse-all buttons.

Resetting

The entire edit list can be reset from the Editing Layers header’s context menu, which resets all adjustments for the current photo.