Imviz: Clarify how subset is extracted when multiple data are loaded (was: explicit layer in subset plugin)

[Jdaviz-Triage-Bot]

Reporter: Camilla Pacifici

Update: See #1629 (comment)

Here is the workflow:

• load two images with overlapping regions, but not on same field of view
  (mast:JWST/product/jw01345-o002_t022_nircam_clear-f200w_i2d.fits
  mast:JWST/product/jw01345-o003_t023_nircam_clear-f200w_i2d.fits)
• select subset in first image in the overlapping region
• check position of the same subset in pixels in the second image
  expected that it is not covering the same object
• link by WCS
• now subset covers the same ra-dec in the two images
• look at image 2 and open subset plugin
  the pixels in the subset do not match what seeing in the image
  this is confusing
• open aperture photometry plugin
  get results with subset on image 1
  results make sense
• blink to image 2
• use photometry plugin with same subset in image 2
  subset still looks somewhere else
  results do not make sense even if I see the subset on the right object

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DISCLAIMER: This issue was autocreated by the Jdaviz Issue Creation Bot on behalf of the reporter. If any information is incorrect, please contact Duy Nguyen

[camipacifici]

Might be fixed by #1524 ... testing

[camipacifici]

Yes! #1524 fixes the photometry problem here.

The confusing output of the subset plugin is still valid. Maybe the subset plugin should also mention the layer where the subset has been created?

[pllim]

Maybe the subset plugin should also mention the layer where the subset has been created?

That might be a bit tricky but maybe @astrofrog can clarify. As far as I can understand, Subset extraction is based on what happens to be the reference data at the time of extraction, and reference data is tied to a particular viewer and can be changed in some circumstances.

[pllim]

p.s. I am going to clarify the Issue title.

[kecnry]

As far as I can understand, Subset extraction is based on what happens to be the reference data at the time of extraction, and reference data is tied to a particular viewer and can be changed in some circumstances.

So similar to how we display the top-layer being referenced in the compass plugin, couldn't we have an indicator showing the current reference layer?

[pllim]

couldn't we have an indicator showing the current reference layer?

We could, but I am not sure about live-updating the Subset plugin.