Hi Chris: I have taken a look at your project file and, indeed, the edge setting is more or less correct. In this case, the intensity below 1A is certainly background and you can see this by plotting the data in R-space with k-weight of 2 or 3 and then slowly increase the Rbkg (I find that 0.02 is a good increment). You will see that there is not much change until you reach Rbkg=1.08 and then the intensity below 1A basically all disappears without affecting the peak sizes or positions of everything above 1A. This indicates to me that it is really a background problem. If you now plot the XMU and the background you will see that the red background line is going through the data much more reasonably. There are certainly other methods to remove this background peak. Everyone has their own methods but I am pretty confident that the result will be the same. an Rbkg of 1.08 is not bad at all. Cheers, Carlo -- Carlo U. Segre -- Professor of Physics Associate Dean for Graduate Admissions, Graduate College Illinois Institute of Technology Voice: 312.567.3498 Fax: 312.567.3494 segre@iit.edu http://www.iit.edu/~segre segre@debian.org