EDNA (Incardona et al., 2009), had the initial goal of automating the sequence of taking reference images, characterising these images and calculating an optimised data collection strategy taking into account user requirements and radiation damage. The short-coming of the current implementation is that if reference images are not optimally collected (for example, using an incorrect exposure time, oscillation width and/or detector resolution) it is difficult, if not impossible, to calculate the optimal data collection strategy. EDNA/BEST can give advice on the optimal detector resolution (Popov & Bourenkov, 2003); however, the user has to manually follow suggested values and restart the collect and characterise pipeline. In this workflow the characterisation pipeline has been enhanced by simply adding the optional step of automatically re-collecting reference images with a different exposure time or oscillation value and detector resolution. If the workflow is run in interactive mode the user can easily intervene and interrupt the workflow at certain stages as well as change the proposed new data collection parameters through prompts displayed in MXCuBE, if needed.

 

The workflow is started by selecting the "Enhanced EDNA" workflow in the Advanced tab and adding to the queue, the following options are then presented for number of images and the complexity of strategy required:

 

mxcube_WF_7.png

 

And then options for the image prefix and directory are presented. On clicking "Continue" 2 reference images are collected. If the current parameters are correct for the calculation of a strategy the strategy will be copied to the queue as with a normal EDNA run. However, if the resolution obtainable is higher or other parameters of the strategy can be enhanced a new set of reference images will be collected with the beamline parameters automatically updated (i.e the detector will be moved to a higher resolution etc.) A new strategy will then be calculated and coped to the queue.