Re: [ccp4bb]: REVISE/ECALC//RANTAN/FFT

[Phraenquex VD <loretta@scripps.edu>]

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Personally, I would go straight to SnB or/and ShelxD, both truly
impressive programs.  They also take care of E-calculation (ShelxD
implicitly).

In the same vein, it really helps to have a really excellent (highly
redundant) peak dataset -- in my experience, that's better for solving
substructures than trying to combine somehow two or three MAD datasets of
average qualilty.  Spend the crystal lifetime collecting that peak
instead. [I anticipate that statement will unleash a storm of protest... 
oh well.] One wavelength (SAD) with solvent flattening is, however,
frequently enough to give interpretable maps as well (with Sharp+solomon,
anyway).

Not exactly a direct answer to your question, but whatever :)  
phx. 


> Dear All,
> 	We have stumbled upon a difficult MAD solution (or non solution as yet).
> We are experimenting with RANTAN. Can I check the the FM_RE calculated 
> by REVISE is converted to EM_RE by ECALC which is on its own fed to 
> RANTAN.
> 
> To find heavy atom sites, one then calculates a map using
> F1=EM_RE PHI=PHIbest_rantan and peaksearches it.
> 
> What I am unsure of is the EM_RE quantity, although derived from anomalous
> diffs, it is entered into FFT as F not DANO.
> 
> While I am on, does anyone have any thoughts or advice about what to play 
> with RANTAN and what constitutes something to get encouraged by?
> 
> best
> Jim
> 
> James H. Naismith                | Research mailto:naismith@st-and.ac.uk
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