The Radial Filter enables you to apply changes to just a selected part of a picture. The adjustments are applied in a circular or elliptical shape.
After activating the Radial Filter tool, you then create a mask. This can normally be done in either of two ways:
- Click the Add Mask button on the right toolbar. This creates an elliptical mask in the middle of the picture. No settings are applied to this mask.
- Click and drag in the picture. A radial mask is placed in the spot where you clicked. (If a mask has already been created, you must hold down Ctrl and click to create another.)
If the picture contains a human face, you can also use a third method—presets. In the Actions category within the Presets section, some presets utilizing AI technology are available:
- AI Radial Filter – Lighten Faces
- AI Radial Filter – Brighten Eyes
- AI Radial Filter – Enhance Mouth
Using one of these presets seeks out all the faces, eyes, or mouths in the picture, and a separate mask is created for each one.
In the middle of each mask, there is a node that can be clicked and dragged to reposition the mask. On the top, bottom, left, and right edges of a mask, there are nodes that can be clicked and dragged to stretch or shrink the mask. An interrupted line runs through these in-preview controls’ middle node; this line defines the mask’s angle. Hovering the mouse cursor by this line shows an icon 
. When this icon is showing, click and drag to change the mask’s angle.
You can add an unlimited number of masks to a picture. Each mask is added to the mask list in the right panel as it is created. Each mask starts out with the name Radial Filter # (the # symbol here represents the mask number). Masks can be renamed—to rename a mask, double-click its name, type the new name, and press Enter or click anywhere outside the name.
Hovering over a mask’s name shows two more buttons on the given row: 
, 
, 
, 
.
Invert Mask – Clicking this adds to the mask everything that was not selected before and removes everything that was previously selected.
Default Mask Settings –The mask retains its shape and position, but all adjustments to the settings are zeroed out.
Duplicate – This creates another mask with the same shape, position, and adjustments to settings.
Delete – This deletes the entire mask and all changes to the given mask’s settings.
With default program settings, besides showing buttons when you hover the mouse cursor over a mask’s name, the program also temporarily changes the picture preview to black and white, and the area of the selected mask remains filled with blue. This makes it easy to check what exactly has been included into the mask, and how the transition looks between the mask and its surroundings. The options for how and when a selection is displayed can be altered after clicking the 
Show Selection button at the top right corner of the right panel.
Two sliders are located under the list of masks created and the Add Mask button:
Use Gradient Width to set the width of the transition (gradient) between the area where changes are being applied and that area’s surroundings. The lower the gradient width, the sharper the transition. The higher the gradient width, the smoother and finer the transition.
Use Rotation to set the mask’s rotation
Below that are functions for Basic Edits, Tone Curve, Color Shift, and Color Overlay.
Show Selection
Clicking the arrow next to the button displays these options: Normal, Inverted, Mask Only, Desaturate, and Show When Editing. With default (normal) settings, the Inverted option is active, alongside Desaturate and Show When Editing..
Normal – Everything that is not included in the selection is covered in a transparent red.
Inverted – Everything that is included in the selection is covered in blue.
Mask Only – everything that is not included in the selection is covered in an opaque red, and everything that is included in the selection is covered in an opaque white.
Desaturate – if this option is active, everything that is not included in the selection is displayed in black and white when the Normal or Inverse option is being used.
Show When Editing – if this option is active, the selection display options are only shown when you are changing the mask’s shape, position, and rotation, or when you are hovering the mouse over a mask’s name. If this is not checked, and is not active as well, the selection is not displayed at all. If it is not checked, but the icon is active, the selection will continue to be displayed.
Keyboard Shortcuts
Ctrl+click into the picture and drag – this creates a new mask.
Ctrl+Alt+click into the picture and drag – this creates a new mask with the same edits as the active mask.
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