The new collimator. (a) Photograph of the new collimator installed on the diffractometer of BL-17A. (b), (c) Comparison of the horizontal and vertical beam profiles at the sample positions. Gray, red and blue represent the profiles of a full-sized focus beam, a beam defined by a slit and a beam defined by the collimator, respectively. The beam profiles were measured by scanning the beams by using a pinhole 20 µm in diameter at the sample position. Fluxes of the beams defined by the slit and the collimator are 2.2 × 109 and 1.7 × 109 photons s−1, respectively, at 12.6 keV. (d) Comparison of the data collection statistics (solid: I/σ; dash: Rmeas) of a thaumatin crystal. Red and blue indicate the statistics of the data sets collected using the slit or collimator, respectively. The data sets were processed using XDS (Kabsch, 2010).