non_etc_requirements.txt

== CALACS/CALWP2 support ==
TENTATIVE: It's not clear what will be the best way to replace synphot
functionality in the pipelines. It could be that adopting an ETC-like
model, where pysynphot queries are sent to a server, would be best; or
it might be best to pre-calculate the necessary quantities into files
that would be managed, thus breaking the dependency on
(py)synphot. For purposes of pysynphot planning, we will assume that
the pipelines will require this functionality, just in case that is
the route that is decided.

Purpose of this release: allow pipelines to survive the demise of
synphot
Pysynphot build: 0.9.x
Acceptance defined as: CALxxx regression tests pass

- Showfiles: already implemented in 17.1

- Provide method(s) on SpectralElement to calculate:

            URESP           Flux (in flam) of a star that produces a response
                            of one photon per second in this passband
            PIVWV           Passband pivot wavelength
            BANDW           Passband rms width
            FWHM            Full width half max of equivalent gaussian
            WPEAK           Wavelength at peak throughput
            TPEAK           Peak bandpass throughput
            AVGLAM          Passband average wavelength
            QTLAM           Dimensionless efficiency
            EQUVW           Passband equivalent width
            RECTW           Passband rectangular width
            EMFLX           Equivalent monochromatic flux



==Subsequent to 18.0 UI==
Purpose of this release: complete core synphot functionality.
Pysynphot build: 1.0
Acceptance defined as: ???

- Provide ColorIndex objects so they can be used in the same way as
  SpectralElement objects

- Provide gauss and lgauss AnalyticSpectralElements

- Provide AnalyticSourceSpectrum type for HI absorption spectra

- Provide a means by which to determine the flux at a particular
  wavelength (analogous to refwave/flux_ref parameters in countrate)