Examples of diffraction images collected at 4.6 keV from Cdc23Nterm crystals of different quality. The images from the Rayonix 225HE detector were displayed with ADXV (Arvai, 2015) using identical contrast levels. The photographs of crystals (a, b, c) were taken with the online camera of the EMBL–Maatel MD2 difffractometer. The yellow circle indicates the beam centre and beam diameter. (a) Illuminating the entire volume of a crystal with a collimated 100 µm diameter X-ray beam. (b) Illuminating one part with a collimated 100 µm diameter X-ray beam. (c) Illuminating one part of the crystal, which gave the data sets, with a collimated 50 µm diameter X-ray beam. (d) The low level of X-ray background obtained at P13 when collecting data at λ = 2.69 Å, as shown in a randomly chosen diffraction image. The inserts show pixel values in the region of the diffraction spot (marked in the yellow square) and the relative pixel counts for the spot series (in the white rectangle).