I'm trying to use experimental phases derived from an cryoEM density map do carry out reciprocal space refinement in phenix.refine. I used phenix.map_box to get the map coefficients, and then the CCP4 program chltofom (with the -colin-phifom flag) to create the HL coefficients from F/PHI computed from the electron density map. 1. If I ask for the mlhl target, I get quite odd target values, e.g. for a 2.9 Å data set: | normalized target function (mlhl) (work): -5862.311069 | | target function (mlhl) not normalized (work): -6438670043.811632 and attempted refinements more or less destroy my protein and increases both the mlhl target value and the R-factors. Is there an example data set I could access to help me find out what I'm doing wrong? (Using the ml target, as suggested in DeMaio et al, Nature Methods 10:1102, 2013, seems to work well, and has a postive target function, but seems sub-optimal if phase information is available.) 2. Is there a way to do a "simple" least-squares refinement, minimizing sum( w_i * |Fobs_i - Fcalc_i|**2 ) where both Fobs and Fcalc are treated as vectors? Does the ls target perhaps do this if use_experimental_phases=True? Usual apologies if there is some great tutorial on this that I've not found. ...thanks...dave case