Applying long wavelength X-ray （ca. longer than 2 Å） in macromolecular crystallography has been limited due to the lack of dedicated measurement environment. Photon Factory BL-1A, as an MX beamline optimized for diffraction experiment using the wavelength from 2.7 to 3.3 Å, offers the opportunity to routinely perform data collection for Native SAD phasing or light atoms identification with much sophisticated manner. Sample optimization is another key for successful experiment at the wavelength where severe absorption is inevitable. We describe how the difficulties in use of long wavelength X-ray were overcome at the beamline and the auxiliary facility, as well as the current results of Native SAD phasing.
