3D refinement resulting map vs Sharpening tool

Dear colleagues,

What is the difference between the sharpened map we get after 3D refinement and the Sharpening tool?

Because after every refinement, there is a recommendation to proceed with the sharpening in the log of CS.
But isn’t we already get the sharpened map available in the output of 3D refinement jobs?

thank you

Sincerely,
Dmtiry

Dear @Dmitry,

The sharpening tool allows you to specify the specific b-factor you would like to sharpen the map to. This is helpful for comparing two maps, because maps sharpened by different b-factors can appear significantly different.

Best,
Michael

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Dear @mmclean ,

Thank you for the answer.

But isn’t the applied b-factor already listed in the final result of 3D refinement?

Or the already applied b-factor is suboptimal and the Sharpening tool is not obligatory, but as Volume tool can be used for changing/testing some parameters?

Kind regards,
Dmitry

Yes, the b-factor is estimated, plotted, and applied at the end of the refinement. However, the estimated b-factor can vary when parameters change (e.g. non-uniform vs homogeneous refinement, marginalization enabled/disabled, etc.). So, the sharpening tool is provided as a way in which you can manually override these b-factors, and sharpen any map to the desired b-factor. When doing careful comparisons between two output maps of the same dataset with different parameters, I will pass them both through a sharpen job with the same b-factor, and download and compare these maps, rather than the ones output by refinement.

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