Lightroom’s New Feather & Edge Mask Controls Explained
AI masking in Lightroom can create an excellent starting point, but the first selection is not always the finished mask. You may find a thin ridge after subtracting an object, a boundary that extends too far, or a transition that simply feels too abrupt.
Fixing those problems has traditionally meant reaching for the Brush tool and carefully painting along the boundary. Lightroom’s Feather and Edge controls offer a faster way to refine many AI-generated masks before doing that manual cleanup
Two Controls That Solve Different Problems
Feather and Edge both change a mask’s boundary, but they do different jobs.
Feather softens the transition between the masked and unmasked portions of the photograph. As you increase it, the boundary becomes more gradual. The adjustment blends across a wider area rather than ending abruptly.
Edge changes the size of the masked area. Move it in one direction and the mask expands. Move it in the other direction and the mask contracts.
That distinction is the key to using these controls well:
Use Feather when the transition is too hard.
Use Edge when the mask includes too much or too little of the photograph.
The Feather and Edge controls appear at the top of the masking area (for tools that support the controls).
Understanding What Feather Does
The easiest way to understand Feather is to view a mask as a white-on-black overlay. White represents the fully selected area, black represents the unselected area, and the shades of gray between them form the transition.
Increasing Feather widens and softens that transition. The mask becomes progressively less defined along its boundary. A large Feather value is not automatically better. Push it too far and the adjustment can spread well beyond the intended subject. The goal is to make the transition believable, not simply make the mask as soft as possible. For example, a softly focused object may benefit from more feathering than a sharply defined rock against the sky. Let the photograph tell you how much softness the mask needs.
Expanding and Contracting a Mask with Edge
Edge controls where the mask’s boundary falls.
Moving Edge in the positive direction expands the selected area. On a sky mask, for example, the selection begins to creep farther into the land beneath it. Moving Edge in the negative direction contracts the mask and pulls it away from that boundary. This is particularly useful when Lightroom’s initial selection is close but not quite right. Rather than immediately painting along the entire edge, you can make a broader correction with a single slider.
Pro Tip: Double-clicking the control’s pin returns Feather or Edge to its default value. Double-clicking the control name itself does not reset it.
Why These Controls Appear on Only Some Masks
Feather and Edge are available for Lightroom’s AI-generated selections, including:
Subject
Sky
Background
People
Landscape
Objects
The controls do not appear as separate controls on every masking tool because several tools already provide equivalent ways to shape their boundaries. A Brush mask already has Feather, while brush size effectively determines its edge. Linear and Radial Gradients have their transitions built into the shapes you draw.
Range masks also have variations on what Feather and Edge do. Luminance Range masks include both edge and transition controls on both the shadow and highlight sides of the selected range. Color Range is a slightly different case. Its Refine control can broaden or narrow the mask’s influence, making it somewhat similar to Edge, but it does not have a separate Feather control. That would be a nice addition, though in practical application a less common need.
The important thing to remember is that Lightroom has not removed boundary control from those other tools. It is simply presented differently because of how each type of mask works.
Cleaning Up Object Subtractions
The Edge control becomes especially useful when subtracting an object from an existing mask.
Suppose I create a mask for several rocks in a landscape but want the adjustment to affect only the midground rocks. I can subtract the foreground rock using an Object mask. Lightroom may identify the object correctly while leaving a thin ridge around the selection.
Previously, I would clean up that ridge with a Brush subtraction. Now I can increase Edge on the Object subtraction and expand it just enough to remove the leftover boundary.
Object subtractions often leave a thin border of pixels behind. Sliding the Edge control to the right quickly takes care of that.
Each mask component has its own Feather and Edge settings. If you subtract several objects separately, you can refine each subtraction according to what its particular boundary needs. One object may need a modest Edge adjustment, while another may need considerably more.
There is still a point where the Brush tool becomes the better choice. Expanding the edge too far can remove part of a nearby object that you want to keep. I prefer to use Edge for the broad cleanup and then reach for the Brush only where more precise work is necessary.
Edge Control and Sky Halos
Edge may also help along a sky boundary, but it is not a complete halo-removal tool.
Halos often appear when a strong adjustment is applied across a high-contrast boundary. The sky selection may be quite accurate, yet a heavy contrast change can still make the transition look unnatural.
Contracting or expanding the mask can sometimes reduce the problem. However, if the adjustment itself is too strong, moving the boundary may only shift the halo rather than eliminate it.
That is where a more selective masking approach becomes useful. Edge is a convenient first adjustment, but complicated sky boundaries may still require additional masks or more precise refinements.
Final Thoughts
Feather and Edge are useful because they let you refine an AI selection before committing to detailed brushwork. Feather softens the transition. Edge expands or contracts the selected area.
For me, Edge is especially helpful when an Object subtraction leaves a narrow ridge behind. A quick adjustment can handle much of the cleanup, leaving the Brush tool for the smaller areas that genuinely require precision.
The goal is not to avoid manual masking at all costs. It is to begin with the broadest effective correction and add detailed work only where the photograph needs it.
Sunrise, Bandon Beach, Oregon
Contact Scott to commission a print or license this image.
Have you ever subtracted an object from a Lightroom mask, only to find a thin ridge left behind around the selection? Cleaning that up usually means reaching for the Brush tool and carefully painting along the edge.
Lightroom Classic’s new Feather and Edge controls give you a faster way to soften, expand, or contract many AI-generated masks. In this video, I’ll explain how the controls work, which masking tools support them, and where Edge is already saving me cleanup time.