[Chimera-users] volume viewer question

[Tom Goddard]

Hi Boaz,

   That approach works too.  Getting the exact threshold isn't really so 
hard using my method though.  If using menu entry Measure Mean, SD, RMS 
reports RMS as 5.3 and I want the contour level to be 2 sigma, then I 
just type in 10.6 (= 2 * 5.3) in the volume dialog threshold level entry 
field and press the Enter key.

     Tom

> Hi William,
>
> The way I go about the sigma level contouring in Chimera, though it's 
> somewhat ham-fisted but perhaps less complicated than Tom's 
> suggestion, is to contour the region of interest at the desired sigma 
> level in Coot or O and then play with the contouring in Chimera until 
> both maps look as similar as possible (the maps rarely look identical 
> for technical differences in the contouring techniques, I think). It 
> works.
>
>    Cheers,
>
>                Boaz