PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM OBJECT = TEXT NOTE = "Comments on the Stardust NAVCAM Annefrank Encounter Archive" PUBLICATION_DATE = 2004-07-02 END_OBJECT = TEXT END Comments on Stardust NAVCAM Annefrank Encounter Archive ======================================================= This document contains comments and errata concerning the Stardust Navigation Camera (NAVCAM) Annefrank Encounter Raw Image Archive (volumes SDNC_0002.) TWIST_ANGLE In the Image Labels and Index ----------------------------------------- The value of the TWIST_ANGLE included in the image labels and index does not follow PDS definition for this angle. Instead, this angle is defined as the angle between the leftward direction (in left-to-right increasing sample number, top-to-bottom increasing line number displayed image) and projection of the EME J2000 reference frame +Z axis onto the image plane, measured clockwise. Flip Required to Achieve ``As Seen By Observer'' Display -------------------------------------------------------- Since the optical path of the camera includes a mirror and the flight and image production s/w do not compensate for the flip that this mirror introduces, the images displayed in normal left-to-right increasing sample, top-to-bottom increasing line fashion have to be transposed (flipped about the left-top/right-bottom diagonal) in order to appear as an observer located on the spacecraft would see it. Non-standard Keywords in Image Labels ------------------------------------- The following keywords used in the image labels have not yet been formally approved and registered in the PDS Dictionary (as of 07/02/04): SCAN_MIRROR_ANGLE SCAN_MIRROR_RATE SCAN_MIRROR_TEMPERATURE EMEJ2000_SC_QUATERNION SATURATED_PIXEL_COUNT Line Terminator in the Attached Image Labels -------------------------------------------- The lines in the PDS labels attached to the images are terminated with LF only while PDS requirement is the CR-LF. PDF Documents ------------- A number of documents in the DOCUMENT directory of this volume are provided only in PDF format because producing a representative ASCII version for them was not possible.