Gctf: Real-time CTF determination and correction

Accurate estimation of the contrast transfer function (CTF) is critical for a near-atomic resolution cryo electron microscopy (cryoEM) reconstruction. Here, a GPU-accelerated computer program, Gctf, for accurate and robust, real-time CTF determination is presented. The main target of Gctf is to maximize the cross-correlation of a simulated CTF with the logarithmic amplitude spectra (LAS) of observed micrographs after background subtraction. Novel approaches in Gctf improve both speed and accuracy. In addition to GPU acceleration (e.g. 10-50×), a fast '1-dimensional search plus 2-dimensional refinement (1S2R)' procedure further speeds up Gctf. Based on the global CTF determination, the local defocus for each…

• WT
  Wellcome Trust
• MR
  Medical Research Council

  Award: MC_UP_A025_1011