Presence and effects

Use clarity, texture, dehaze, vignette, halation and grain to adjust detail and finishing effects.

These controls follow colour adjustments and precede crop. Amounts default to zero and display hundredths. Each effect can be masked and included in a look.

Clarity and texture. Clarity adjusts local contrast at 3% of the long edge, weighted towards midtones. Texture uses a finer 0.4% radius. Negative values soften. Both affect luminance without shifting colour, and limit edge changes to half a stop to avoid dark halos.

Dehaze. Positive values reduce local haze and restore contrast; negative values add haze. The effect uses the coarse local radius to distinguish smooth haze from detailed foreground.

Vignette. Positive values darken corners; negative values lighten them. The elliptical falloff follows the crop and straighten angle. Midpoint and feather are fixed. On a layer, the crop-based vignette is limited by its mask. With crop, mask or repair tools active, the full-frame preview uses a full-frame vignette; closing the tool restores the crop-based result.

Halation. Adds a warm glow around bright highlights, using a soft threshold and a blur radius of 2% of the long edge. Photographs without highlights are unchanged. Brightness above white retains its proportional contribution. Monochrome uses a neutral glow. Hue is fixed.

Grain stock and format. Click the stock and format row below the Grain slider to open the grain popover. Use its two menus to choose a stock and format, with a preview below. Stocks are grouped by emulsion family and speed:

• Black and white 100, 400, 1600 and 3200, labelled Fine, Medium, Coarse and Soft.
• Colour negative 160, 400 and 800.
• Slide 100 and a pushed 1600 stock.

Formats are 35mm, 6×4.5, 6×6, 6×7 and 4×5. Grain size follows the ratio of the stock’s clump size in micrometres to the format’s long edge in millimetres. The same stock therefore appears finer on a larger format.

Grain and tonality. Grain strength already responds to each pixel’s luminance. The renderer measures that luminance in stops below white and applies a smooth, stock-specific tonal curve. Most negative stocks are strongest around 2.5 stops below white, in the lower midtones; slide grain peaks around four stops below white, deeper in the shadows. Grain fades at true black and clipped white. Grain amount cannot be negative.

Tonality changes the strength of the grain, not its size, placement or number of grains per cell. Stock and Format determine its scale; the photograph’s seed determines its pattern. There are currently no separate shadow, midtone or highlight grain controls.

A possible extension is an editable tonal strength curve in the grain popover, letting the user shape where grain appears while retaining the chosen stock’s texture. Making grain size or the number of grains respond to tone would be a separate extension. Neither extension is implemented.

The model places three varied grains per clump-sized cell. Nearby grains form clumps and short chains. Colour stocks separate three dye layers: colour negative has the strongest colour speckle, with slide and pushed stocks between that and neutral black-and-white grain. Changing colour separation preserves luminance noise. Monochrome always renders grey grain.

Stable pattern. Each photograph gets its own seed, and repeated renders of the same recipe produce the same pattern. Copying a treatment copies its seed. Older treatments without a seed share a default pattern.

Controls. The Amount slider preserves Stock and Format; each menu preserves Amount. Choosing Stock or Format before raising Amount is remembered while the photograph stays open. Changing photographs discards an uncommitted choice. Controls follow the selected layer or look, reset with the group and are disabled under ORIGINAL.

Grain preview. The strip below the popover’s menus shows grain on a ramp from four stops below white to near white, at one physical display pixel per rendered pixel. It previews at Amount 50 when the current amount is lower, with a label explaining this. It also reports grain-cell size in current-render pixels, or that grain is subpixel and visible in export. During slider dragging the strip stays still, then updates on release. The popover stays open while you adjust the Grain slider in the sidebar. Click the stock and format row again to close it. Monochrome previews use grey grain.

Canvas and export. Grain position and scale are tied to the photograph. At matching resolution, canvas and export agree. When grains are smaller than a canvas pixel, their visible amount decreases as grains are averaged together.

The current canvas can still exaggerate subpixel grain relative to a resized export. Judge large-format grain from an export and check the preview’s pixel-size label.

Lightroom import. Texture, Clarity, Dehaze, post-crop vignette and grain amounts map to these controls. Vignette signs are converted to preserve darkening. GrainSize selects the nearest black-and-white speed on 35mm. Non-default GrainFrequency is reported as unsupported when grain is active. Pre-crop vignette is unsupported and reported.