darkroom on darktable 5.6 user manual

clipping warning

Mon, 01 Jan 0001 00:00:00 +0000

Highlight areas of the image that may exhibit luminance or gamut clipping.

When an image is sent to a display device, each pixel is normally represented as a set of 3 numbers, representing the intensity of the red, green and blue primary colors in the output color space. Because the output color space is usually closely related to hardware with physical limitations, there is a maximum permitted value for the [R,G,B] channels, representing the maximum available intensity for that color space. Similarly, there is also a minimum value below which pixel values will be mapped to zero. When we try to convert from a larger color space to the final output color space, any values exceeding this maximum will be clamped to the maximum value, and any values below the minimum will be clamped to zero. This process is called “clipping” and it will lead to lost detail, or “incorrect” colors for any pixels with clipped channels.

color assessment

Mon, 01 Jan 0001 00:00:00 +0000

Assess colors and brightness in your image under neutral viewing conditions to avoid perceptual issues.

When developing an image, the way we perceive brightness, contrast and saturation is influenced by the surrounding ambient conditions. If an image is displayed against a dark background, this can have a number of adverse effects on our perception of that image:

Exaggeration of the perceived exposure makes the image seems brighter than it really is. This is nicely illustrated by the Adelson checkerboard shadow effect.
A decrease in the perceived saturation in the image makes the colors seem less rich than they really are (the Hunt effect).
A decrease in the perceived contrast in the image makes the tones seem flatter than they really are (Bartleson-Breneman effect 3)

The end result is that the final image can end up being too dark and overly-processed in terms of contrast and color saturation. To avoid this, the color assessment module in the darktroom places a grey and white frame around the image to help the user better assess the colors in the image

duplicate manager

Mon, 01 Jan 0001 00:00:00 +0000

View and create multiple versions of the current image. Each version can be edited independently without affecting other versions – all versions use the same underlying image file, but the editing history of each version is stored in its own independent XMP sidecar file.

The duplicate manager lists each version of the current darkroom image along with its preview thumbnail. Hold down the left mouse button on a thumbnail to temporarily show that version in the center view. Double-click to switch to that version and edit it.

gamut check

Mon, 01 Jan 0001 00:00:00 +0000

Highlight areas of the image that may exhibit gamut clipping.

Click the icon to activate the gamut check display mode for your image. This function highlights, in cyan, all pixels that are out of gamut with respect to the selected softproof profile. You can also activate gamut check with the keyboard shortcut Ctrl+G. A message “gamut check” on the bottom left of your image tells you that you are in gamut check display mode. Gamut check and soft proof are mutually exclusive modes.

global color picker

Mon, 01 Jan 0001 00:00:00 +0000

Take color samples from the current darkroom image, display their values in multiple ways and compare colors from different locations.

The color picker is activated by pressing the picker icon. The module’s parameters will remain in effect until you leave the darkroom mode.

Besides the global color picker described here, many darktable modules (e.g. tone curve) also contain local pickers which are used to set individual module parameters. You should be aware that these two forms of picker do not always work in the same color space. The global color picker works in the histogram color space and takes its samples after the complete pixelpipe has been processed. Local pickers run in the color space of the module in which they are activated and reflect the input or output data of that module within the pixelpipe.

guides & overlays

Mon, 01 Jan 0001 00:00:00 +0000

A number of commonly-used compositional guides can be overlaid on your image while you are editing. These can be enabled either globally (all the time) or locally (when certain modules are active).

Other darkroom functionality also draws colored overlay lines on the image (for example, drawn masks). An option is also provided to change the color of those overlays (see below).

🔗global guides

Left-click the icon in the bottom bar to globally display guide overlays. The overlays will remain switched on until you click the button a second time to switch them off.

high quality processing

Mon, 01 Jan 0001 00:00:00 +0000

Process the image in the darkroom view using “high quality mode”, so that the displayed image reflects the appearance of a full-sized export.

Activate this mode by clicking the icon at the bottom of the darkroom view.

Note that while this mode provides the most accurate representation of the processed image, it also results in significant performance degradation. Please see the types of pixelpipe section for a full discussion.

history stack

Mon, 01 Jan 0001 00:00:00 +0000

View and modify the history stack of the current darkroom image.

This module lists every change of state (activate/de-activate/move/change parameters) for all processing modules that have been modified for the current image. Select a point in the stack to return to that point in the development history of the image. Shift+click an item in the history stack to expand that module in the right-hand module panel without changing the current edit.

image information line

Mon, 01 Jan 0001 00:00:00 +0000

Display information about the current image in a darkroom panel.

The contents of this line can be set in preferences > darkroom. See the variables section for information about the variables that can be used here. You can also insert a newline with $(NL).

The image information line can be displayed in the top, bottom, left or right panel depending on an additional configuration item in preferences > darkroom.

mask manager

Mon, 01 Jan 0001 00:00:00 +0000

Manage all drawn masks and shapes for the current image.

This module can be used to create, rename, edit and delete shapes. You can alter the shapes in a drawn mask, group shapes together, and combine them using set operators.

The top line of the mask manager panel contains buttons that can be used to create new shapes. These are the same as in the drawn mask interface of the processing modules.

module order

Mon, 01 Jan 0001 00:00:00 +0000

Change the order of the processing modules in the darkroom using presets.

When processing an image, the active modules are applied in a specific order, which is shown in the right-hand panel of the darkroom view. This module provides information about the current ordering of the processing modules in the pixelpipe. The name of the currently-selected preset is shown in the module header (or “custom” if the user has manually modified the order). The following presets are available for selection.

navigation

Mon, 01 Jan 0001 00:00:00 +0000

Zoom and pan the current image.

The navigation panel (displayed on the top left hand side of the darkroom) shows a full preview of the current image with a rectangle showing the area that is currently visible in the central panel. You can interact with this module using your mouse in the same way as you can interact with the main image (scroll to zoom in/out, middle-click to cycle through zoom levels, click+drag to pan). Alternatively, the current zoom scale is displayed in a combobox to the bottom-right of the preview – click to choose from a number of common zoom levels or type a number to set the zoom level manually.

raw overexposed warning

Mon, 01 Jan 0001 00:00:00 +0000

Highlight areas of the image where color channels of the raw input file are clipped.

Clipped color channels imply an overexposed image with loss of information in the affected areas. Some of this information may be recoverable using the highlight reconstruction, color reconstruction or filmic rgb modules.

Click on the icon to show/hide the warning overlay. Right-click on the icon to open a dialog containing the following configuration parameters.

mode

Choose how to mark clipped areas:

mark with CFA color: Display a pattern of the respective primary colors (red, green, and blue) to indicate which color channels are clipped.

mark with solid color: Mark clipped areas with a user defined solid color (see below) independent of the affected color channels.

false color: Set clipped color channels to zero in the affected areas.

color scheme

Choose the solid color for the mark with solid color mode.

clipping threshold

Set the threshold defining what values are considered to be overexposed. You can safely leave this slider at its default value of 1.0 (white level) in most cases.

snapshots

Mon, 01 Jan 0001 00:00:00 +0000

Store development snapshots and compare with the current edit.

Snapshots can be taken at any point in the development process and later overlaid onto the current center view or shown side-by-side. This allows you to undertake a comparison (by default left=snapshot, right=active edit) while you are tuning parameters of a module. It can also be combined with the history stack module to compare a snapshot against different stages of development.

To take a snapshot, click on the take snapshot button. Above the button you will see a list of the snapshots that have been taken for this editing session. The name of each snapshot reflects the name of the module selected in the history stack and its position at the time the snapshot was taken. You can choose your own label for a snapshot by Ctrl+clicking on the snapshot name – this will be displayed after the module name, separated with a bullet.

soft proof

Mon, 01 Jan 0001 00:00:00 +0000

View your image rendered using a selected color profile.

Click the icon to activate the soft proof display mode on your image. This allows you to preview your image rendered using a printer profile to see how colors will end up on the final print. You can also activate soft proof with the keyboard shortcut Ctrl+S. A message “soft proof" on the bottom left of your image tells you that you are in soft proof display mode.