tso_aperture_photometry forces use of photom step in calwebb_image2

[stscijgbot-jp]

Issue JP-3895 was created on JIRA by Taylor Bell:

At present, a ValueError is raised if someone tries to run the tso_phometry step on calints files that were run without the photom step. The choice to raise this error is largely arbitrary, seems to have been made 5 years ago when making some preliminary code for NIRCam photometry, and is relatively simply generalized to work with different input data units. For time-series analyses, it is generally preferred not to run the photom step as only the relative variations in flux are of interest, but this current assertion prohibits the skipping of the photom step.

 

Relevant lines that raise this ValueError can be found at:

jwst/jwst/tso_photometry/tso_photometry.py

Lines 62 to 63 in 7b4e8d4

	if datamodel.meta.bunit_data != 'MJy/sr':
	raise ValueError('data is expected to be in units of MJy/sr')

[stscijgbot-jp]

Comment by Taylor Bell on JIRA:

I've discussed this with Sarah Kendrew, and will use some of my functional time to resolve this issue and some other issues with calwebb_tso3 which was why I had assigned myself to this ticket. I'm new to the institute and to Jira though, so maybe the Assignee field means something other than what I'd assumed

[stscijgbot-jp]

Comment by Tyler Pauly on JIRA:

In general, changes to the pipeline code must be reviewed by the JP Coordination team before they are merged. New tasks are assigned to the JP lead, David Law, for review and prioritization before they are worked.

You are welcome to make a PR against the repository changing this behavior if you like, but review and merging will wait for David's approval.

[stscijgbot-jp]

Comment by Taylor Bell on JIRA:

Gotcha, thanks for the clarification!

[stscijgbot-jp]

Comment by David Law on JIRA:

Taylor Bell I'd like to understand this a little better; for imaging TSO the photometric calibration should simply be a constant scaling factor, so why is it useful to skip the photom step?  Presumably the use case here is for external users who want to make light curves in DN/s?