Fair enough to ask, but I think your question has understatus for the ccp4bb, indeed - you will find information of basic matters of protein crystallography in any text book on the subject - including also the nature of anomalous scattering and how it is exploited by data collection around absorption edges. You cannot do crystallography and get and evaluate proper results without studying the basic theory and practice - crystallography is science after all, not black-box analysis.

Poul