urn:nasa:pds:context:instrument:nac.mr6 1.0 1.8.0.0 Product_Context 2017-09-22 1.0 Initial PDS4 version. urn:nasa:pds:context:instrument_host:spacecraft.mr6 instrument_to_instrument_host Danielson, G. E. and D. R. Montgomery (1971), Calibration of the Mariner Mars 1969 Television Cameras, J. Geophys. Res., 76, 2, 418 - 431, doi:10.1029/JB076i002p00418. reference.DANIELSON_MONTGOMERY1971 Rindfleisch, T. C., J. A. Dunne, H. J. Frieden, W. D. Stromberg and R. M. Ruiz (1971), Digital Processing of the Mariner Mars 1969 Pictures, J. Geophys. Res., 76, 2, 394 - 417, doi:10.1029/JB076i002p00394. reference.RINDFLEISH_ETAL1971 MARINER 6 Narrow Angle Camera Imager not applicable The Narrow Angle (NAC) camera had Schmidt-Cassegrain reflector optics without filters. The narrow angle f/2.4 lens had a focal length of about 504 mm. The optics focused images onto a vidicon to obtain images of Mars. The vidicon was etched with a 7 x 9 grid of reseaux to aid in computing the geometric distortions in the digital images. The NAC produced 945 sample by 704 line, 8 bit/pixel digital images after ground processing to produce the image archive.