Hi, Tom, Pavel and Joe,

> I'm glad you put that option in, Pavel.  However for model-
> building it is not so straightforward. Normally we are building into density-modified
> maps. Density modification works poorly when a significant set of
> reflections is excluded, so this becomes impractical.

As I remember it was a paper (by Blanc, ..., Bricogne ? am I wrong? Ifailed to find it right now) where they faced exactly this problem.Again, as I remember they suggested to exclude the test-set reflectionsfrom the map calculation but , to minimize the map deformation, insteadof them include average Fobs for the corresponding resolution shell.

Is it a way to answer the original question / problem ?

As I understand, a similar technique Pavel already uses to calculate the maps with Fobs missed.

Best regards,

Sacha