Unsharp mask
The Unsharp Mask is Photoshop's classic sharpening filter, which accentuates edges by raising the contrast around them. The name comes from the darkroom, despite what it sounds like it really does sharpen. Three sliders control amount, radius and threshold.
Choose Filter, Sharpen, Unsharp Mask and set Amount for the strength, Radius for the width of the edge accentuation and Threshold to spare noise. A small radius sharpens fine detail, a larger one adds more local contrast. Apply it to a smart object or a separate layer so you can dial it back later. Tip: zoom to 100% to judge the effect honestly, otherwise you quickly oversharpen.
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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.