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mperrin / webbpsf

James Webb Space Telescope PSF simulation tool - NOTE THIS VERSION OF REPO IS SUPERCEDED BY spacetelescope/webbpsf
BSD 3-Clause "New" or "Revised" License
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Consider adding nonzero default pupil shear for coronagraphs based on ISIM CV measurements #158

Closed mperrin closed 6 years ago

mperrin commented 7 years ago

From JWST-RPT-028027 (the ISIM CV pupil shear final report), the current best estimates for pupil alignments in ISIM are: MIRI: -1.2% shift in V2, 1% in V3. NIRCam: 0.2% in V2, -2% in V3 from PAR measurement; -0.1% in V2, 0.1% in V3 from PIL measurement. (See the above cited report for discussion of the discrepancies between the two measurement methods)

The NIRCam coronagraph Lyot masks are sized to accommodate misalignments and there should not be much effect on the contrast. For MIRI the Lyot masks are not undersized and the impact of misalignment is larger. We should consider updating the default setup for coronagraphic observations to take this into account.

Likewise we could also consider adding in the pupil rolls for each instrument. These are of order 0.6%, in some cases a bit larger.

mperrin commented 6 years ago

This task has been folded into the plan for #204