PDS_VERSION_ID = PDS3 LABEL_REVISION_NOTE = "2009-06-08, Gutierrez 2009-06-18, Gutierrez, Updated per comments by R. Chen 2010-07-19, Gutierrez, Updated CONFIDENCE_LEVEL_NOTE Added reference to SIS Added reference to calibration data set 2010-10-06, Gutierrez, Fixed line length 2017-07-17, Joy, Corrected peer review liens; 2017-07-26, Joy, Final updates;" OBJECT = DATA_SET DATA_SET_ID = "DAWN-X-FC1-3-RDR-CRUISE-IMAGES-V1.0" OBJECT = DATA_SET_INFORMATION DATA_SET_NAME = "DAWN FC1 CALIBRATED CRUISE CHECKOUT/CALIB IMAGES V1.0" DATA_SET_TERSE_DESC = "Reduced data records for Framing Camera 1 on Dawn during the Initial Checkout and Cruise Phases" DATA_SET_COLLECTION_MEMBER_FLG = N START_TIME = 2007-09-27T00:00:00 STOP_TIME = 2011-03-16T22:00:00 PRODUCER_FULL_NAME = "PABLO GUTIERREZ-MARQUES" DATA_SET_RELEASE_DATE = 2017-07-26 DETAILED_CATALOG_FLAG = N DATA_OBJECT_TYPE = "IMAGE" CITATION_DESC = " Nathues, A., H. Sierks, P. Gutierrez-Marques, S. Schroeder, T. Maue, I. Buettner, M. Richards, U. Chistensen, U. Keller, DAWN FC1 RAW (EDR) CRUISE CHECKOUT/CALIBRATION IMAGES V1.0, DAWN-X-FC1-2-EDR-CRUISE-IMAGES-V1.0, NASA Planetary Data System, 2017." ABSTRACT_DESC = " Abstract ======== Framing Camera 1 is one of two identical units flying on Dawn spacecraft. This dataset includes the Reduced Data Record (RDR) version of all available images acquired during the initial checkout and pre-Vesta cruise phases (Checkout, Earth to Mars, and Mars to Vesta). As in the original Raw data sets, in addition to the imagery, ancillary information is stored within the image headers, as well as a detailed account of all the reference files used for the calibration. Calibration files needed for further processing are archived as a separate data set. " DATA_SET_DESC = " Dataset overview ================ Framing Camera 1 is one of two identical units flying on Dawn spacecraft. This dataset includes the Reduced Data Record (RDR) version of all available images acquired during the initial checkout and pre-Vesta cruise phases (Checkout, Earth to Mars, and Mars to Vesta). As in the original Raw data sets, in addition to the imagery, ancillary information is stored within the image headers, as well as a detailed account of all the reference files used for the calibration. Calibration files needed for further processing are archived as a separate data set. The images in this dataset have been radiometrically calibrated by means of fully reversible procedures, transforming the value of the pixels from digital units to applicable engineering units without modification of the geometry. For more information on the contents and organization of the volume set refer to the aareadme.txt file located in the root directory of the data volumes. Parameters ========== Compression: FC images may optionally be compressed by wavelet transformation. Wavelet compression: Images may be integer or floating point wavelet transform-compressed in the DPU. The integer approach produces lossless compression, while the floating point can induce distortions of +/-1 DN. The encoding of the wavelets ensures that any length of the data starting at the beginning can be decoded, thus allowing to compress further by discarding the trailing part. Windowing: In order to manage downlink resources, up to 10 portions of the image can be selected in the DPU and downlinked as subframes. The subframes are allowed to overlap. During EDR construction each subframe is stored separately and also mosaicked into the original image. Exposure Control: The exposure time of FC images is set by command for each image. Pointing: The Framing Cameras are fixed mounted onto the Dawn Instrument deck, with the nominal alignment of the optical axis with the +Z axis of the spacecraft. Deviations from the nominal are documented in the calibration data. Filter selection: The FC has 8 filters at its disposal, numbered from F1 to F8. F1 is a broadband (clear) filter, sensitive in the wavelength interval from 400 to 1100 nm peaking at 700 nm. The narrow-band color filters are of the interference type, and have wavelengths ranging from 430 to 980 nm. Processing ========== An FC image downlinked by the spacecraft unpacks into a succession of one or more compressed image subframes with an attached PDS headers containing housekeeping items that include full status of the instrument hardware, software configuration, temperature, voltage and current readings. The data in one EDR consists of one or more reconstructed image frames, with the accompanying header translated into text format in the label. The dimensions and location (pixel coordinates) of each frame are included for proper further processing. Each frame is formatted into one file (suffix *.IMG), with an attached label. Subframes are retained as separate entities and also are reassembled into their original coordinates in the 'summary' image. Parts of the reconstructed image not included in the subframes are given a value of zero. The label contains all relevant housekeeping information in calibrated form (e.g. degrees Celsius, volts, or amperes. For further details on the layout of the data and the possible combinations of frames, please refer to the Software Interface Specification. The calibration process is divided into several steps that aim to remove the effect of different source of noise: conversion from 16-bit integer to 32-bit floating point, read-out bias, dark current, read-out smear, flat field non-uniformity, correction of under-sensitive pixels, exposure normalization, radiometric calibration. For more detailed information on the calibration process, please refer to [SCHROEDER&GUTIER2011]. For a discussion of which calibration images to use for a given activity, please refer to the data set catalog file for DAWN-CAL-FC1-2-EDR-CALIB-IMAGES-V1.0. " CONFIDENCE_LEVEL_NOTE = " Exposure times ============== Due to an idiosyncrasy of the proximity electronics, that takes approximately 193 milliseconds from the commanding of the image acquisition to the actual start of the exposure, the images report the commanding time and the end of exposure. This results in a difference of 193 milliseconds between the usual calculation of exposure time (STOP_TIME - START_TIME) and the reported EXPOSURE_DURATION, which is always shorter than the difference of the other two. Calibration files ================= All the files involved in the calibration of this data set have been subsequently delivered as part of the calibration data set. Furthermore, the history part of the PDS header of each image lists which calibration files was used for each of the calibration steps. All the files delivered in the calibration data set are final. Even if images acquired later in time will require a different calibration file, this will be added to the data set but not replace the old one. " END_OBJECT = DATA_SET_INFORMATION OBJECT = DATA_SET_TARGET TARGET_NAME = "STARFIELD" END_OBJECT = DATA_SET_TARGET OBJECT = DATA_SET_TARGET TARGET_NAME = "MARS" END_OBJECT = DATA_SET_TARGET OBJECT = DATA_SET_TARGET TARGET_NAME = "SATURN" END_OBJECT = DATA_SET_TARGET OBJECT = DATA_SET_TARGET TARGET_NAME = "1 CERES" END_OBJECT = DATA_SET_TARGET OBJECT = DATA_SET_TARGET TARGET_NAME = "20 CEPHEI" END_OBJECT = DATA_SET_TARGET OBJECT = DATA_SET_TARGET TARGET_NAME = "CANOPUS" END_OBJECT = DATA_SET_TARGET OBJECT = DATA_SET_TARGET TARGET_NAME = "VEGA" END_OBJECT = DATA_SET_TARGET OBJECT = DATA_SET_TARGET TARGET_NAME = "42 PEGASI" END_OBJECT = DATA_SET_TARGET OBJECT = DATA_SET_TARGET TARGET_NAME = "EPSILON GEMINORUM" END_OBJECT = DATA_SET_TARGET OBJECT = DATA_SET_TARGET TARGET_NAME = "HR 2290" END_OBJECT = DATA_SET_TARGET OBJECT = DATA_SET_HOST INSTRUMENT_HOST_ID = DAWN INSTRUMENT_ID = "FC1" END_OBJECT = DATA_SET_HOST OBJECT = DATA_SET_MISSION MISSION_NAME = "DAWN MISSION TO VESTA AND CERES" END_OBJECT = DATA_SET_MISSION OBJECT = DATA_SET_REFERENCE_INFORMATION REFERENCE_KEY_ID = "SIERKSETAL2011B" END_OBJECT = DATA_SET_REFERENCE_INFORMATION OBJECT = DATA_SET_REFERENCE_INFORMATION REFERENCE_KEY_ID = "SCHROEDER&GUTIER2011" END_OBJECT = DATA_SET_REFERENCE_INFORMATION END_OBJECT = DATA_SET END