Object mask
With the object mask in Lightroom you select a specific object by roughly brushing over it or drawing a box around it. The AI then works out the precise edges of that object for you. Handy for things that aren't a recognisable subject or sky, like a car, a building or a flower.
This is the answer when 'Select subject' doesn't quite grab what you want: you point out which object it is yourself. Brush roughly over the object or draw a rectangle around it, and Lightroom does the rest. You can then refine the mask by adding and subtracting. Tip: use separate object masks to give different elements in your photo their own treatment each.
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The presets on this site set these adjustments up for you as a starting point, which you then fine-tune to taste.