User stories are a useful input to developing the concept for a software product and specifying the features. Typically, the stories have a lead off description of the form "As a (kind of user) I want to (do something) to (achieve something)." The elaboration of the user stories describe what inputs are needed, what outputs are expected, and what computations are performed. 



Candidate user stories

TopicAuthorComments

Identify associated data sets

e.g. Find and download direct and dispersed images that overlap on the sky via an archive query
Organization and bookkeepingConventions for file formats (in and out) metadata in files, file names, directory structure, output files (e.g. column names and units)
Geometric transformationsNorbert PirzkalOutline all of the variants and what the use cases are (e.g. elaborate from Nor's presentation)
Astrometric registrationAlign dithered observations
SimulationsCreate a simulated 2D dispersed spectrum from a 1D spectrum and image morphology.
Background subtractionWhat are the different background components & approaches to estimating/subtracting for HST instruments?

Flatfielding

Flatfielding with broad-band flat

This can be subtle; the same approach can't be used in all circumstances. Maybe multiple user stories are needed? 

(Ivelina Momcheva can describe the rationale of using the broad band flat field)

1D simple extractionHarry Ferguson
1D model-based extractionHarry Ferguson
2D spectral extraction
Maybe multiple stories with different approaches to getting a 2D extracted dispersed spectrum?
Co-adding 
Maybe several stories with different approaches to co-adding spectra taken at different orientations?
Find an isolated emission lineEM2D use case
Create an emission-line mapCreate a 2D emission-line map from spectra taken at different orientations (this may require multiple stories?)
Fit a set of templates

Varying flux and redshift

Identify overlapsBased on a known object catalog + grism exposure, generate a list of objects that can contribute spectra to a given sky position.