Due to its high-efficient, white output, xenon is used extensively for photographic applications, despite its great expense. In lasers, spectral-line emission is usually favored, as these lines tend to better match absorption lines of the lasing media. Krypton is also occasionally used, although it is even more expensive. At low current-densities, krypton's spectral-line output in the near-IR range is better matched to the absorption profile of neodymium-based laser media than xenon emission, and very closely matches the narrow absorption-profile of Nd:YAG. None of xenon's spectral lines match Nd:YAG's absorption lines so, when pumping Nd:YAG with xenon, the continuum radiation must be used.