MicroED datasets of hemin and biotin microcrystals were collected using Talos Arctica (200 kV) with the CMOS camera Ceta. The stage was controlled using SerialEM and diffraction images were independently collected using Velox software. For this reason, only frames with constant rotation speed should be used for data processing. Rotation step (continuous) was ~1.52°/frame and each dataset consisted of ~40 images (tilt range is +/-30°). The calibrated camera length using Al powder was 793.52 mm. Biotin crystals belonged to space group P212121 with a~5.2, b~10.2, c~20.8 Å. ~14 datasets could be merged at ~0.85 Å resolution. Hemin crystals belonged to space group P-1 with a~10.6, b~11.1, c~13.8 Å, α~107.1°, b~99.5°, c~107.9°. ~12 datasets could be merged at ~0.9 Å resolution. Collection conditions: biotin: gun lens 8.0, spot 11, C2: parallel beam condition, 0.039e/A^2/sec, total ~3.5e/A^2 hemin: gun lens 4.0, spot 11, C2: parallel beam condition, 0.095e/A^2/sec, total ~8.6e/A^2 Note: emd files (hdf5 format) were transparently compressed using h5repack -f SHUF -f GZIP=4 command to reduce file size. EMD file can be processed with DIALS using this dxtbx format file. Metadata (machine parameters, stage tilt angles etc.) is stored as json format in /Data/Image/*/Metadata in emd file. See here for details. If you want to process data using DIALS, please see the processing note.