.. index:: PSF model (VIS); Calibration observations .. _calobs-vis-psfcalibration: **CALPRODUCT-VS-019:** VIS PSF Calibration ========================================== .. include:: definitions.rst Parent requirement ------------------ Not in the `CalCD-B `_ Scheduling ---------- There is no required numeric cadence for the PSF calibration fields. Rather, it is determined by the reference survey design (RSD) itself, in particular the major thermal disturbances due to large slew angles. The current best effort approach is to have a PSF calibration field aligned with every wide survey patch. Roughly, a PSF calibration field would be observed once every 1 or 2 months, but with a large scatter. Time-critical ------------- No. Objective --------- Calibrate / validate the VIS PSF Model, using stars in the same magnitude range (17.5 < VIS < 21) as in the wide survey. The S/N must be 5x that of the wide survey. Fulfilled by ------------ :ref:`calobs-block-f-selfcal` (providing further constraints on a monthly basis) :ref:`calobs-block-f-vis-psfcalibration` :ref:`calobs-block-f-contaminationscan` Data volume ----------- ``100*VS = 45200 MB`` Processing input ---------------- :command:`Ground Processing Input Data`: TBD :command:`Data Description`: 100 VIS science exposures Processing output ----------------- TBD Required accuracy, constraints ------------------------------ images successfully acquired Processing tools ---------------- TBD Quality control parameters -------------------------- DataModel: ``_ Contact person -------------- VIS instrument scientist .. raw:: latex \clearpage