Hi,
I processed my data set in cryosparc - I used the pixel size for the data that was collected (0.954A/pixel) and after processing the data in cryosparc, the pixel size of the map is twice (1.9A/pixel) that of the size that the data was collected. Also the FSC plot did not converge. Do you have any suggestion as to what I am doing wrong? I am attaching the FSC-plots. Thanks in advance.
What were the extraction parameters - Extraction box size, Fourier cropping?
Box size was app twice the particle diameter 520 Angstrom and the Fourier cropping 300 Angstrom, particle diameter was app 260 Angstrom.
if you are fourier cropping 520–>300 A, your output pixel size will be 0.954*(520/300)=1.65Å, so this result is expected - you are hitting Nyquist (resolution limited by sampling).
Also, which job type is this from? If it is from heterogeneous refinement, you would expect to see this regardless, as heterogenous refinement by default uses a smaller box for speed (default of 256x).
Thanks, so the problem is the Fourier cropping?
It’s not a problem per se - it is often beneficial for speed to do this in the earlier stages of processing. But once you get to this point, you probably will want to re-extract without fourier cropping, yes.
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