Xie Jiabao wrote:
Dear all,
I am using the density modification tool in ccp4 to generate improved phases
for/from my model. I find that the electron density map I generate using Fobs,
and density modified phases (PHIDM) are not the same as that generated using
Fobs, phicalc (original calculated phases) and FOMDM (new improved figure of
merit post dm). Can someone please explain to me why this is so?
Thanks in advance,
Xie
The calculated map is a fourier transform of h k l W*F, PHI
So if youwant a DM style map you need to input
F=Fobs W=WDM PHI=PHIDM . Density modifiction will change phases and
weights..
( I think DM may also put out a term FDM which equals WDM*FOBS so you
could use F=FDM, PHI=PHIDM))
I dont know what PHICALC is but if you use that phase you must use its
associated weight
Eleanor
