摘要： The Orion high-resolution X-ray (OHREX) imaging spherically bent crystal spectrometer, operated with both image plates and CCD cameras, provides time-averaged plasma diagnostics through high-resolution spectroscopy with good signal-to-noise at the Orion laser facility. In order to provide time-resolved spectra, the OHREX will be out?tted with a streak camera, and in this case, even higher signal to noise will be desired. Using the OHREX’s sister instrument, the EBIT High-resolution X-ray (EBHiX) spectrometer, at the LLNL electron beam ion trap EBIT-I, we therefore compare the ef?ciency of a high-quality Ge (111) crystal (2d = 6.532 ?) with that of a higher integrated re?ectivity, but lower-resolution highly annealed pyrolytic graphite (HAPG) crystal (2d = 6.708 ?) in the energy range 2408–2452 eV. We ?nd that the HAPG provides overall more signal across the entire image; however, because of the much better focusing properties of the Ge crystal, the latter provides more signal within the central 100 μm of the spatial pro?le in the cross-dispersion direction and is thus more suitable for the narrow entrance window of the Livermore-built streak camera.