urn:nasa:pds:vl_image_raw:calib:gainoff 1.0 1.21.0.0 Product_Ancillary 2024-05-13 1.0 Initial version. 1976-07-20Z 1982-11-05Z Viking Mission urn:nasa:pds:context:investigation:mission.viking ancillary_to_investigation Viking Lander 1 Host urn:nasa:pds:context:instrument_host:spacecraft.vl1 is_instrument_host Camera 1 for VL1 Instrument urn:nasa:pds:context:instrument:cam1.vl1 is_instrument Camera 2 for VL1 Instrument urn:nasa:pds:context:instrument:cam2.vl1 is_instrument Viking Lander 2 Host urn:nasa:pds:context:instrument_host:spacecraft.vl2 is_instrument_host Camera 1 for VL2 Instrument urn:nasa:pds:context:instrument:cam1.vl2 is_instrument Camera 2 for VL2 Instrument urn:nasa:pds:context:instrument:cam2.vl2 is_instrument gainoff.tab 1997-07-01 0 4 The data in this table are used to compute the photosensor array output voltage from an image digital number (DN). The data are taken from Huck et al., Radiometric Performance of the Viking Mars Lander Cameras, NASA TM X-72692, 1975. Voltage is computed as follows: v = (2**GN)*(DN/4)/Kg + K1*OFN - K2 where v = voltage in units of volts, GN = gain number from the PDS image label, DN = digital number from the image, Kg = gain constant, K1 = offset constant 1, OFN = offset number from the PDS image label, and K2 = offset constant 2. The digital number is divided by 4 because the original data returned from the spacecraft were 6-bits in length and then converted to 8-bits by multiplying by 4. The constants in this table vary by a small amount as a function of gain, offset, and temperature. These small variations are discussed in Wolf et al., Viking Lander Camera Radiometry Calibration Report, JPL Pub. 77-62, 1977. Carriage-Return Line-Feed 6 0 40 lander_number 1 1 ASCII_Integer 2 The Viking Lander number, either 1 or 2. camera_number 2 4 ASCII_Integer 2 The camera number on one of the Viking Landers, either 1 or 2. instrument_serial_number 3 8 ASCII_String 5 The manufacturer's serial number assigned to an instrument. It is used to uniquely identify an instrument in tracing its components or determining its calibration history. gain_constant 4 15 ASCII_Real 8 The value for Kg in the DN to voltage equation for Viking Lander image data. offset_constant_1 5 24 ASCII_Real 8 The value for K1 in the DN to voltage equation for Viking Lander image data. offset_constant_2 6 33 ASCII_Real 6 The value for K2 in the DN to voltage equation for Viking Lander image data. gainoff.lbl 0 PDS3 Carriage-Return Line-Feed