patch pseudo metrology for GUIDE3 and GUIDE7 into fp-metrology.csv

desihub / desimeter

DESI coordinates and transformations

BSD 3-Clause "New" or "Revised" License

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patch pseudo metrology for GUIDE3 and GUIDE7 into fp-metrology.csv #108

Closed ameisner closed 4 years ago

ameisner commented 4 years ago

This pull request includes code and files that patch in Gaia-based pseudo metrology for GUIDE3 and GUIDE7.

julienguy commented 4 years ago

It should not change the results but the internal values of x_gfa,y_gfa of the CCD corners in write_guide3_guide7 are not actually CCD pixel coordinates (because of a mix between focal surface coordinates of the images of stars, and coordinates of CCD corners which are not on the focal surface; discussion continued offline).

ameisner commented 4 years ago

@julienguy I updated my methodology to take into account your recommended transformation between coordinates on the focal surface and the physical CCD. The resulting GUIDE3/GUIDE7 'metrology' values are changed by substantially less than 1 micron in all cases.

julienguy commented 4 years ago

thank you aaron