Setting XYZLIM in CCP4's fft should work. Cheer, Robbie Sent with my Windows Phone ________________________________ Van: Ian Clifton<mailto:[log in to unmask]> Verzonden: 7-12-2015 16:17 Aan: [log in to unmask]<mailto:[log in to unmask]> Onderwerp: Re: [ccp4bb] map covering several unit cells Boaz Shaanan <[log in to unmask]> writes: > The 'run fft' task in ccp4i has an option 'extent defined by user', > isn't that what you're looking for? The program 'extend' used to do > this but this is the current implementation of this function I guess. There’s also the program MAPMASK, which might also do what you want. -- Ian ◎