Re: [ccp4bb]: contour ?

[Bart Hazes <bhazes@ualberta.ca>]

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On Wed, 5 Sep 2001, Gosu RamaChandraiah wrote:

> 	Hi,
>
> 	Given a effective resolution of the data, at what contour one has
> to examine the mixed fourier synthesis map (2Fo-Fc & Fo-Fc) ?
> 	Is there any relation between resolution, completeness & contour ?
>
> 	With regards
> 	GOSU

The simple answer is that you want to contour at a level that gives the
clearest view of the density. I normally contour 2Fo-Fc & Fo-Fc at 1 and 3
sigma, respectively, but in some parts of the map you want to lower the
contour level. Your density will most likely not be equally strong throughout
the map due to variations in B-factor or missing strong low resolution terms,
so you'll have to adjust contour levels. If you lower the contour level too
much you'll be blinded by all the noise features. Just use your eyes to tell
what works best.

Bart Hazes

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