Answered
Noice masking in detal panel
On the iPad I have the full detal panel with noice masking but on a Mac it's not there. This is Lightroom not classic.
It sounds like you haven't expanded the various options in the Detail panel to show the sub-options. If so, click on the small triangle to the right of Sharpening, Noise Reduction, Color Noise Reduction to show/hide the other sliders.
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