.. index:: Phase diversity; Calibration observations .. _calobs-vis-phase-diversity: **CALPRODUCT-VS-017:** VIS Phase Diversity ========================================== .. include:: definitions.rst Parent requirement ------------------ Not in the `CalCD-B `_ Scheduling ---------- Once, during PV phase, and subsequently before the beginning of routine observations. Time-critical ------------- No Objective --------- The primary objective of these observations is to determine the wavefront for the VIS weak lensing experiment, as a function of various thermal states depending on AA and SAA. Stellar fields will be observed with the telescope being both defocused and focused. High S/N is required in the stellar images. Fulfilled by ------------ :ref:`calobs-block-pv-phase-diversity` :ref:`calobs-block-f-phase-diversity` Data volume ----------- TBD Processing input ---------------- :command:`Ground Processing Input Data`: TBD :command:`Data Description`: TBD Processing method ----------------- TBD Processing output ----------------- PSF model Required accuracy, constraints ------------------------------ TBD Validation ---------- VIS: The analysis of the phase diversity data is a substantial manual off-line task done by OU-SHE, and the validation / success criteria are not available at this time. Results are expected only once we are well into the routine phase observations, at which point a phase diversity campaign will not be repeated lightly. Quality control parameters -------------------------- DataModel: ``_ Contact person -------------- Calibration Lead .. raw:: latex \clearpage