Re: [ccp4bb] Refinement with twinned data question

2011-10-02 Thread Yuri
  

1-So for my case, I should try and generate Rfree flags, in the
higher apparent C 2 2 21 and not the real P 1 21 1, correct?
2-I noticed
that if I used the output PHIC FOM data, the maps looked awesome! Too
good almost... 

Thanks a lot 

On Sun, 2 Oct 2011 12:07:22 +0100, Garib
N Murshudov wrote: 

> Dear Yuri 
> 1) For twin refinement refmac
internally changes free reflections so that twin related reflections
belong to the same class (twin or working). However it would be good to
generate free reflections in higher space group that would include twin
and space group symmetries. 
> 2) You should always use original data
for refinement. Never use output from refmac for next round of
refinement. Output mtz file is representation of model. 
> regards 
>
Garib 
> 
> On 2 Oct 2011, at 03:27, Yuri wrote: 
> 
>> Dear all,
>> I
have some questions about the correct protocol for refinement of twinned
data (0.46)
>> 
>> 1- How do I ensure that my Rfree set is generated
properly?
>> 
>> 2-I noticed that if I enable intensity based twin
refinement, refmac estimates the correct twin fraction
>> law -h,-k,h+l.
But for subsequent refinement rounds should I keep using the raw
intensity mtz file or
>> the newly generated mtz with PHIC and FOM
information?
>> 
>> Thank you
>> -- 
>> Yuri Pompeu
> 
> Garib N
Murshudov 
> Structural Studies Division 
> MRC Laboratory of Molecular
Biology 
> Hills Road 
> Cambridge 
> CB2 0QH UK
> Email:
ga...@mrc-lmb.cam.ac.uk [1] 
> Web http://www.mrc-lmb.cam.ac.uk [2]

--

Yuri Pompeu
  

Links:
--
[1] mailto:jen...@mrc-lmb.cam.ac.uk
[2]
http://www.mrc-lmb.cam.ac.uk/


Re: [ccp4bb] Refinement with twinned data question

2011-10-02 Thread Garib N Murshudov
Dear Yuri

1) For twin refinement refmac internally changes free reflections so that twin 
related reflections belong to the same class (twin or working). However it 
would be good to generate free reflections in higher space group that would 
include twin and space group symmetries. 
2) You should always use original data for refinement. Never use output from 
refmac for next round of refinement. Output mtz file is representation of model.

regards
Garib
 
On 2 Oct 2011, at 03:27, Yuri wrote:

> Dear all,
> I have some questions about the correct protocol for refinement of twinned 
> data (0.46)
> 
> 1- How do I ensure that my Rfree set is generated properly?
> 
> 2-I noticed that if I enable intensity based twin refinement, refmac 
> estimates the correct twin fraction
> law -h,-k,h+l. But for subsequent refinement rounds should I keep using the 
> raw intensity mtz file or
> the newly generated mtz with PHIC and FOM information?
> 
> Thank you
> -- 
> Yuri Pompeu

Garib N Murshudov 
Structural Studies Division
MRC Laboratory of Molecular Biology
Hills Road 
Cambridge 
CB2 0QH UK
Email: ga...@mrc-lmb.cam.ac.uk 
Web http://www.mrc-lmb.cam.ac.uk





[ccp4bb] Refinement with twinned data question

2011-10-01 Thread Yuri

Dear all,
I have some questions about the correct protocol for refinement of 
twinned data (0.46)


1- How do I ensure that my Rfree set is generated properly?

2-I noticed that if I enable intensity based twin refinement, refmac 
estimates the correct twin fraction
law -h,-k,h+l. But for subsequent refinement rounds should I keep using 
the raw intensity mtz file or

the newly generated mtz with PHIC and FOM information?

Thank you
--
Yuri Pompeu