[Chimera-users] Comparison of cryo-em maps

[Elaine Meng]

Hi Dmitry,
Depends what you mean by “compare.”

Some thoughts are: 

(A) subtract one map from the other to see the differences: command “vop subtract”
<http://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/midas/vop.html#subtract>

(B) show the same isosurface level for both, Measure Volume and Area (under Tools… Volume Data) or the corresponding commands “measure volume” “measure area”

<http://www.rbvi.ucsf.edu/chimera/docs/ContributedSoftware/measurevol/measurevol.html>
<http://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/midas/measure.html#volume>
<http://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/midas/measure.html#area>

(C) morph between their isosurfaces with Morph Map tool or command “vop morph"
<http://www.rbvi.ucsf.edu/chimera/docs/ContributedSoftware/morphmap/morphmap.html>
<http://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/midas/vop.html#morph>

This tutorial has an example of morphing between two EM maps (about halfway down the page):
<http://www.rbvi.ucsf.edu/chimera/data/tutorials/eman07/chimera-eman-2007.html>

I hope this helps,
Elaine
-----
Elaine C. Meng, Ph.D.                       
UCSF Chimera(X) team
Department of Pharmaceutical Chemistry
University of California, San Francisco

> On Feb 28, 2020, at 1:58 AM, Dmitry Semchonok <Semchonok at gmail.com> wrote:
> 
> Dear colleagues,
> I have similar cryo-em maps that have also some differences.
> I want to compare them.
> Is there a tool in chimera that can compare the cryo-em maps?
> Thank you!
> Sincerely,
> Dmitry