PPT Slide
VCT Literature References
"Collection and analysis of powder diffraction data with near-constant counting statistics", I. C. Madsen and R. J. Hill, J. Appl. Cryst. (1994). 27, 385-392 http://www.iucr.org/cgi-bin/paper?hz0014
Philips Friendly Fortran source code that does this Madsen and Hill method is at:
http://www.ccp14.ac.uk/ccp/ccp14/ftp-mirror/csirominerals-anon-ftp/pub/xtallography/variable-count-time/
(Original Madsen and Hill VCT (variable count time) Paper), I. C. Madsen and R. J. Hill, Adv. X-ray Anal. (1992), 35, 39-47
W. I. F. David, Accuracy in Powder Diffraction, Abstract P2.6 NIST Special Publication No. 846, Page 210, (1992) National Institute of Standards and Technology, Gaithersburg, MD, USA.
Vctconv will convert Madsen and Hill VCT format into GSAS ESD format
- http://www.ceramics.irl.cri.nz/Convert.htm