Masking

[<naismith@st-andrews.ac.uk>]

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Dear All,
	Any imaginative solutions?
We have a dimer in the asu and have good matrices to relate the monomers 
(straight 180 rotn). The starting map is to say the least a little poor.

Is there a way to harness the averaging to generate a better map from 
which to derive the solvent mask?

Effectively a single run of maskless averaging.

I kind of thought by using maprot (mode correlation) and mapmask that it 
should draw a mask around the dimer (proper ncs) which would serve as a 
solvent flattening mask. The resulting mask is dismal and the one from DM 
which I assume is calculated on the unaveraged map is much better. The 
underpining assumption is that the single run averaged map is a better 
place to derive a solvent flattening mask from that the starting map.

(The ncs mask can be simply made by putting an atom of 40A radius at the 
centroid of the heavy atom position. On our tests this is about as good 
as a monomer mask)

Any comments/suggestions

best
Jim


James H. Naismith                | Research mailto:naismith@st-and.ac.uk
Centre for Biomolecular Sciences | Teaching mailto:jhn@st-and.ac.uk
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