Hi Smith,

In line with the question of Xun, will you please introduce a way to scale-up the intensity of cryo-EM to the level of intensity of x-ray crystallography?

map comparison does not care where maps come from. You give it two maps on the same gridding (same gridding is essential, obviously) and it tells you pairs of contouring levels that will show equivalent representations of your maps.

I have a read a paper, in which the author have done the above-mentioned scaling-up in order to use the phenix reciprocal space refine for cryo-EM data refine,

Normally, you should not use reciprocal spare refinement when working with cryo-EM maps as your data, cryo-EM map, is in real space. And if you use real-space refinement it does not matter on what scale the input map is as it rescales it internally anyway.

Currently with the availability of pheinix.real_space_refine, in a lot of situations reciprocal refine for cryo-EM data is still necessary.

I would be interesting to hear about those cases!

Pavel