EM quality assurance workflow

The image end result of a cryo-EM study is a three-dimensional density map in which the different parts of the volume may present different degrees of quality (resolution) as a result of, most typically, flexibility or compositional differences of the macromolecule under consideration. Consequently, maps are better described using the concept of local (per voxel) resolution, rather than by a single global value. However, the concept of what resolution truly means is not simple, and several approaches have been proposed to measure resolution (for a review on resolution measures in cryo-EM, see 1).

The existence of different methods to calculate resolution, each included in different software packages, provided a very good case for Scipion Web Tools, a web application built over Scipion framework software that offers access to predefined image processing workflows over the web.