Fig. 8.

Robustness test of CTF determination using varying resolution cutoff or estimated astigmatism as input. (a) Typical CryoEM micrograph of HAV was selected and systemically examined to test the robustness of Gctf. The blue points represent results by high resolution cutoff and the red points by low resolution cutoff. (b) The input values of astigmatism ranging from 10 Å to 10,000 Å were used as initial estimation for CTF determination. All input values in this range generated almost identical results. Therefore, there is no need for optimizing the input astigmatism in this case. Blue and red lines represent defocus U and V respectively. Green line represents the azimuthal angle.