Hello all, I have a couple of comments about LSF in Athena and I would like to hear other people's opinions on the matter. Also, it would be interesting to know: are there many people who use Athena to do LSF? I found that there is some inconsistency with plotting after the fit is done. In my case nonzero energy shifts are applied to the fitted data and the standards. The resulting linear combination fit doesn't look shifted in energy appropriately - visually there is a mismatch between the data and the fit. On the other hand, R-factor and Chi^2 are very reasonable. This looks somewhat confusing. Also, in my experience the obtained fractions in Athena come out slightly different from those I could get using Sixpack LSF software. In my fits I used the same constrains/options, same data and references and same data range. What can be the cause of this? Stanislav Stanislav Stoupin ----------------------------- Research Assistant/PhD student BCPS department Illinois Institute of Technology email: stousta@iit.edu voice: 312-567-7983