Subtract masking

A masking technique in adobe-lightroom used to exclude specific areas from an existing mask, enabling highly targeted Local adjustments.

Used to refine selections by removing unwanted pixels from a previously defined mask.
Works as part of a suite of masking-tools (including add-masking and intersect-masking) to achieve precision.
Often used in conjunction with intersect-masking (introduced late 2023) to isolate specific overlapping regions for complex edits.

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