Extended Data Fig. 1: Automated targeted data collection flowchart.

a, The workflow of ArbitrEM, including two steps: target selection and automated data collection. (i) Low-magnification images are firstly acquired to identify holes where tubes are present, and these holes are selected by marking the holes in the images (red crosses); (ii) The images of selected holes are acquired at hole-magnification, centered, and converted into anchor maps; (iii) The acquisition points are marked on anchor maps (boxes), and the beam-image shifts to target the individual acquisition points are calculated. (iv) After all the targets are marked on the hole magnification images, the microscope uses the anchor maps and applies the total beam-image shifts (the stage shift combined with the target-specific beam-image shift) to acquire the high magnification movies. b, A typical low-magnification cryoEM image of CypA-stabilized WT CA assemblies. Scale bar, 2 μm. c, High-magnification image of CypA-stabilized WT CA tubular assembly, illustrating tubes are variable in diameter and easily deformed. d, Gallery of targeted images collected using ArbitrEM. Scale bars, 50 nm.