CryoSPARC Guide

Job: Import Particle Stack

Import particles.


  • Import a stack of particles with metadata and CTF parameters.


  • .star, .mrc, .txt, .par, and/or .emx

Common Parameters

  • It is best to specify the Raw pixel size (A), Accelerating voltage (kV), Spherical aberration (mm) and Total exposure dose (e/A^2) if known
  • Data Sign: [dark-on-light] +1 for dark particles on light background, [light-on-dark] -1 for light particles on dark background. Cryo-EM data is typically recorded as +1 but is often inverted during processing, negative stain EM data is typically recorded as -1'


  • Imported particles

Common Next Steps

  • 2D Classification to sort and classify particles and remove "junk" particles. Or, if the particle stack is already "clean", ab-initio reconstruction can be used to generate one or more initial models which can then be refined