The small-angle X-ray scattering beamline X33 of the European Molecular Biology Laboratory (EMBL) at the DORIS III storage ring [Deutsches Elektronen Synchrotron (DESY) Hamburg] was used for more than two decades to study the structure of non-crystalline biological systems. During recent years the beamline's scope has changed and is now predominantly used to analyze solutions of biological macromolecules. Owing to renewed interest in solution scattering studies from the biological community, the workload on the beamline has steadily increased. A major upgrade of X33 was performed to improve the beamline stability and data quality, to shorten the measurement time and to ensure user-friendly operation. The upgrade involved all major components of the beamline, including the optical system (monochromator, mirror, slits, beam monitors), electronics, control and acquisition software, X-ray detector system and the sample environment. The upgrade improved the brilliance by a factor of about three and the measuring time was reduced by a factor of seven. The knowledge and experience gained during the implementation of the upgrades to X33, may aid the design process for the BioSAXS beamline to be constructed for the PETRA-3 facility at DESY.

A new apparatus and technique to determine the absolute energy of X‐rays from a synchrotron source were used to establish the absolute energy of the zinc metal K absorption edge [9661.1(2) eV] and to measure systematic errors in the angular settings of a typical rotation table used for X‐ray spectroscopy. These errors have a period of 1° associated with the worm gear of the rotation table and should provide a warning to other synchrotron radiation spectroscopists that systematic errors exist in experimental data. The technique relies on determining the orientation of a static silicon crystal with respect to the incoming beam by establishing degenerate reflections with differing Miller indices. Absolute energies can be determined for X‐rays with energies greater than 6 keV. An analysis of the system shows that the technique is also useful for the accurate characterization of the monochromator resolution.

A setup is presented for automated high-throughput measurements of smallangle X-ray scattering (SAXS) from macromolecular solutions on the bendingmagnet beamline X33 of EMBL at the storage ring DORIS-III (DESY, Hamburg). A new multi-cell compartment allows for rapid switching between in-vacuum and in-air operation, for digital camera assisted control of cell filling and for colour sample illumination. The beamline is equipped with a Pilatus 1 M-W pixel detector for SAXS and a Pilatus 300 k-W for wide-angle scattering (WAXS), and results from the use of the Pilatus detectors for scattering studies are reported. The setup provides a broad resolution range from 100 to 0.36 nm without the necessity of changing the sample-to-detector distance. A new optimized robotic sample changer is installed, permitting rapid and reliable automated sample loading and cell cleaning with a required sample volume of 40 ml. All the devices are fully integrated into the beamline control software system, ensuring fully automated and user-friendly operation (attended, unattended and remote) with a throughput of up to 15 measurements per hour.

The EMBL Hamburg Outstation currently operates five synchrotron beamlines for protein crystallography. The strongest of these beamlines is the fixed-energy beamline BW7B which receives about half of the radiation (1.5 mrad) from a 56 pole wiggler located at the DORIS III storage ring at the German synchrotron facility DESY. Over the last years this beamline has been upgraded and equipped with a fully automated crystallographic end-station and a robotic sample changer. The current set-up allows for remote operation, controlled from the user's area, of sample mounting, centering and data collection of pre-frozen crystals mounted in Hampton-type cryovials on magnetic caps. New software and intuitive graphical user interfaces have been developed that control the complete beamline set-up. Furthermore, algorithms for automatic sample centering based on UV fluorescence are being developed and combined with strategy programs in order to further automate the collection of entire diffraction data sets.

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