Tiefen und Lichter Filter

@georg_1772 things change around in Photoshop. I teach my students the Levels way as it's the most easiest for them to learn as the main chunk is doing other Photoshop stuff. Use the Input Levels black slider (the small triangle below the histogram). Hold down Alt (Windows) or Option (Mac) while dragging the slider. This turns the image black, and the white pixels that appear show you exactly which areas are being clipped to pure black. This visual feedback is often more accurate than any numerical value. https://youtu.be/PD3HwMOuprE?si=VQdApRoyGkAYSK2-  

If you prefer using Curves, you can adjust the bottom-left point (the black point) of the curve. Dragging it horizontally sets the clip point, and dragging it vertically affects the darkness. If you need color-specific clipping, you can adjust the curve for the Red, Green, or Blue channels individually. The cool thing that curves offers the highest level of non-destructive control.