search

eslavich / jirahub-sandbox

0 stars 0 forks source link

Implement user-selectable three-position secondary dither pattern within NIRISS WFSS mode #20

Open eslavichjgbot opened 5 years ago

eslavichjgbot commented 5 years ago

Issue JP-500 was created on JIRA by Alicia Canipe:

The NIRISS team is requesting the implementation of optional three-position "secondary" dither patterns for the NIRISS WFSS observing mode (https://jira.stsci.edu/browse/JSOCINT-165).

Is it necessary to generate new science simulations to validate these changes, or would OTB data be sufficient (OTB data has no science pixels, so it is not good for validating the calibration pipeline)?   Note: whenever this mode is implemented, a test case will be added in the OTB . This will take about 3 hours, accounting for meetings to organize the OTB tests.

eslavichjgbot commented 5 years ago

Comment by Kevin Volk on JIRA:

Yes this will require a simulation to test, at least in principle.  Such a test case can be generated in Mirage (one assumes) once the APT is updated for this option.  For the pipeline it seems that the only question is whether the associations are generated properly, and if so then the option should run in the usual way whether there are 2 or 4 direct images.  None the less, an explicit test is needed.  One needs actual simulated data because the point is to pick up stars in the direct images that will produce spectra on the detector, and so the test would need to check whether the "extra" sources are catalogued and associated with the spectra correctly.

eslavichjgbot commented 5 years ago

Comment by Kevin Volk on JIRA:

Once the change is in APT, and assuming that by then Mirage is able to simulate NIRISS WFSS observations (this is currently being added to Mirage), my best estimate is that it would take somewhere between 0.5 and 1 day of work to generate a test case, simulate it, and then try it in the pipeline.  Right now I am not familiar with the source catalogue generated by the WFSS direct images in the pipeline, so it may take some time to experiment to be sure of what the pipeline is doing.

If Mirage is not able to make (good quality) simulations for NIRISS/WFSS we would need to use the grizli code, and that would take longer as I would need help from Swara Ravanranath or others to generate the grism scene images and then put these into Mirage.

 

eslavichjgbot commented 5 years ago

Comment by Howard Bushouse on JIRA:

Related to this change, but a different sub-topic: will this change to observing scenarios require any changes in how the data are processed by the calibration pipeline? On the surface it appears that it does not, because it's only adding a sub-dither pattern to the direct images obtained as part of a WFSS sequence and the creation of a combined image from those dithers should happen automatically within the existing ASN and CAL pipeline infrastructure. But it would be good to have confirmation of this from the instrument team.

eslavichjgbot commented 5 years ago

Comment by Kevin Volk on JIRA:

I think that this should not affect the pipeline processing.  The DMS associations should include all the sub-positions of the dithered images and as long as this is the case the pipeline should run as intended.

eslavichjgbot commented 5 years ago

Comment by Howard Bushouse on JIRA:

(y)