New preprint from the lab: "High-resolution cryo-EM using beam-image shift at 200 keV." Take home message: even with a pretty poorly aligned #cryoEM instrument, you can overcome these aberrations computationally with #RELION (1/n) biorxiv.org/content/10.110…
This came from me asking many people: what is the limit for using beam-image shift to collect data at 200 keV? Everyone said it should be worse at 200 keV than 300 keV but we were surprised no one had benchmarked this yet
So! @annotated_sci set to it - collecting an aldolase dataset on our Talos-Arctica. A part of this work was that we did not do any microscope alignments day-of, simulating what a 'worse case' scenario could be for the instrument.
@annotated_sci We collected over a 10um x 10um area giving us a wide range of images with different beam-image shifts 
@annotated_sci These big beam-image shifts definitely caused some significant aberrations on the micrographs. In some cases, it caused serious objective astigmatism (right)
@annotated_sci These beam-image shifts definitely introduced aberrations. We could only get a structure of aldolase to 5.6Å initially (!). But, after repeated CTF refinement and particle polishing in #RELION, we could increase the resolution from 5.6Å to 2.8Å. Very impressive #RELION!
@annotated_sci Take home messages 1: microscope aberration correction can really overcome microscope alignment issues!
@annotated_sci 2: you can have a lot of aberrations in your dataset and still get good 2D class averages. So- use a lot of beam-image shift for fast data collection and don't touch the microscope if your screening all day!
