Typical beam sizes for an experiment with the X-ray beam larger than optical beams, imaged on a Ce:YAG scintillator screen mounted at the sample position. (a) X-ray beam (100 µm × 100 µm). (b) 785 nm laser excitation spot (50 µm). (c) Spectroscopic collection area in the focal plane, imaged by reverse illumination through the collection branch (200 µm). (d) Computer-generated overlay of all spots.