Dear Matt and dear all,
seems that my original message has been cut by the mailing server. I try 
again, this time without attachments.

I have encountered an issue processing oversampled EXAFS data with 
Larch. In my example the energy step is 0.33 eV in all parts of the 
scan, including the EXAFS. When I use the default procedure in Larch 
(pre_edge and then autobk), I get the noise level in chi(k) that is 
higher than I would expect.  Strangely, rebinning of mu(E) using 
rebin_xafs function does not help, and even increases the noise. The 
lowest level of noise can be obtained when rebinning the data in k 
(starting from the "raw" oversampled chi(E) provided by Larch). In this 
last case, the result is noise-wise very similar to Athena's default.

I think that the high level of noise after the default Larch processing 
can be due to the fact that Larch does not seem to do averaging when 
converting the data from E to k. Instead, it does interpolation with 
UnivariateSpline which by design is not supposed to decrease the noise 
when applied to oversampled data. Is this correct? Would it be worth 
changing?

The reason why the rebinning in E does not decrease the noise is not 
clear to me. Do you have any idea?

Has anyone run into similar issues? Any comments and suggestions are 
welcome.

Thank you

Best regards,
Kirill