[ccp4bb] on Rwork and Rfree

[Dialing Pretty]

Dear All,
 
After we refine the structure of the protein to satisfactory with 
satisfactory Rwork and Rfree, we pick water by phenix refine, and I find Rfree 
always increases slightly after the water picking refinment. 
 
Do you have nay idea to solve this problem or any comment?
 
Cheers,
 
Dialing