Will converting a feathered product selection to a path preserve its soft edge?

What Gets Lost

A selection can contain different coverage values across an area. A feathered edge is one example: pixels near the boundary may be only partially selected, so an operation can affect them gradually. A path describes the boundary as a one-dimensional outline. It does not carry every two-dimensional selection value.

When GIMP converts the selection to a path, the path follows the selection boundary. That makes the outline useful for shape-based work, but the feather information is discarded during conversion. The path is therefore not a storage format for the original selection's edge softness.

Illustrative Exercise

Illustrative exercise: work on a test copy of a product image and preserve the approved original. Create one selection around a box with a deliberately soft edge. Keep that selection available, then convert the selection to a path and convert the path back to a selection. This is a fictional procedure for reasoning about the documented behavior, not a completed software test.

Compare the returned selection with the original along a curved corner or diagonal edge. The original has partial coverage near the feathered boundary. The returned selection has an all-or-none boundary: pixels are either selected or not selected. The outline may be recognizably similar, but the graded transition is no longer present.

The acceptance condition is clear: pass the path route only if the returned all-or-none selection still contains the information your next operation needs. Stop the conversion route if the edge must remain partially covered. In that branch, keep and use the original feathered selection instead of relying on the path to restore it.

1. Duplicate or otherwise create a test copy before experimenting; retain the approved original.
2. Create the feathered product selection on the test copy and keep it as the reference state.
3. Convert that selection to a path using GIMP's selection-to-path operation.
4. Convert the resulting path back to a selection using GIMP's path-to-selection operation.
5. Inspect the same edge region in the original selection and the returned selection.
6. If partial edge coverage is required, stop and return to the preserved original selection. If only the boundary shape is required, continue with the path.

Choose by Information

Choose a path when the product's boundary shape is the important part of the task. A path can represent that outline for later path-based work, but the documented conversion behavior does not make it a backup of the feathered selection.

Choose the selection when partial coverage matters. This includes a feathered product edge where a gradual transition is part of the intended result. Keeping the selection avoids asking the path conversion to preserve information it cannot represent.

This is a workflow decision, not a claim that one object is universally better. Editorial diagnosis: before converting, name the information you must retain. If the answer is shape, a path may be appropriate. If the answer is coverage strength, preserve the selection.

Scope and Safeguards

The documented behavior supplied here applies to GIMP 3.0's conversion between selections and paths. It does not establish identical behavior for another application or version. No additional control is documented here for retaining discarded feather values during selection-to-path conversion.

Do not delete the original selection or replace the approved image while deciding. Keep the original selection and work on a test copy until the edge comparison has a clear pass or fail outcome. If the returned selection is all-or-none and that fails the task requirement, the corrective action is to retain the original selection, not to repeat the same conversion.

Use this question’s review worksheet

The sample rows are fictional exercise data. Preserve the example, save a working copy and record your own inputs, observations and decisions. The example is not a test receipt.

Illustrative manual comparison worksheet (CSV)