Hi Bradley, It seems to me that you can get pretty close to what you're asking for by a combination of "fit marked groups" and "fit all combinations." If you were to take a few representative scans and "fit all combinations" you could discover which constituents were actually present in the set. Then choose those as your standards and "fit marked groups." You could use PCA (newly added to Demeter Athena--yay!) to make this even more robust, by first ascertaining how many constituents are varying between the whole sample set. --Scott Calvin Sarah Lawrence College On Jul 5, 2012, at 12:15 PM, BradleyW Miller wrote: Hi, If my memory is correct there was a period of time you were taking request for improvements on Athena. This may be too late however I would like to see the LCF function of Athena capable of running multiple models (sequential models e.g. Sample A followed by B, C...) using a similar set of standards. For instances, I may have 25-40 spectra (environmental samples), one set of standards which may be plausible, and currently I have to run the model wait for the LCF model for sample A to finish before starting Sample B. If there was a way to write a script or add the functionality of multiple scans from the same set of standards, I (and maybe others) could set up a computer and leave for several hours instead of returning every 5-30 mins to execute a new LCF model. A conversation was posted about running models with a large number of standards (and whether it was appropriate), similarly running multiple samples is cumbersome.