FSC calculation

Submitted by Clara on Tue, 2016-09-13 04:49

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Frealign

Hi,

I would like to know how the splitting of particles is performed in Frealign in order to calculate the FSC and if the data is refined independently as in the "gold-standard" approach.

Thank you very much!

niko Tue, 2016-09-13 08:05

The dataset is split into even and odd-numbered particles to calculate the two maps used for the FSC calculation. All particles are refined against a single reference map. The resolution of the data used during refinement is limited to a user-defined value to obtain an unbiased resolution estimate beyond this limit. The resolution limit should ideally be chosen to be below the estimated resolution from a previous refinement iteration. This usually guarantees that the resolution (estimated by the FSC) extends also beyond the set resolution limit in the next refinement iteration and should therefore be an unbiased resolution estimate.