| Description: A Boolean flag (true, false) indicating whether a coronagraph was used for this observation. For HST products, this attribute is generally derived from the value of the FITS keyword APERTURE. For ACS/HRC products, the coronagraph is in use if APERTURE is HRC-CORON1.8, HRC-CORON3.0, or HRC-OCCULT0.8. This also corresponds to the FITS keyword OBSTYPE being set to CORONAGRAPHIC. For STIS products, a coronagraph is in use if APERTURE is 52X0.2F1, 52X0.2F1-R, 50CORON, or begins with either "BAR" or "WEDGE". For NICMOS/NIC2 products, a coronagraph is in use if APERTURE is NIC2-CORON. This attribute is always false for HST instruments that do not have a coronagraph. |