Bad resample_spec results for MIRI LRS fixed-slit nodded exposures

[stscijgbot-jp]

Issue JP-3624 was created on JIRA by Howard Bushouse:

Help Desk ticket INC0200735 ([https://stsci.service-now.com/nav_to.do?uri=incident.do?sys_id=21db911a834e8ad05d629da6feaad3fa)] reported an issue with the resample_spec results for obs 5 in program 3786, which is a standard MIRI LRS fixed-slit nodded pair of exposures. Obs 11 in the same program is setup identically and the results for that are fine. The problem appears to be related to the way the output WCS grid is setup for the combined output image from resample_spec, such that the two input (cal) images are being combined on top of one another, without the dither/nod being taken into account. A quick look at the WCS information in the exposures for both obs 5 and 11 shows they are very similar, with all the expected ~1.9 arcsec differences in pointing between the 2 exposures in each observation. So the question is why the 2 exposures from obs 11 are being combined properly, with appropriate shifting/alignment due to the dither offset, while obs 5 is not.

[mcara]

What is the relationship between this issue and #8485?