urn:nasa:pds:context:instrument:mcdonald.harlanjsmith_2m7.p45a_phot 1.0 1.16.0.0 Product_Context urn:nasa:pds:context:instrument:mcdonald.smith2m7.p45a_phot 2021-12-07 1.0 per RMS, deprecated mcdonald.smith2m7 in favor of mcdonald.harlanjsmith_2m7 urn:nasa:pds:context:telescope:mcdonald.0m91 instrument_to_telescope urn:nasa:pds:context:telescope:mcdonald.harlanjsmith_2m7 instrument_to_telescope urn:nasa:pds:context:telescope:mcdonald.struve2m1 instrument_to_telescope Binzel, R.P. and J.D. Mulholland, Photometry of Pluto during the 1982 opposition, Astron. J. 88, 222-225, 1983. McDonald P45a Two-Channel Photometer Photometer The McDonald P45a Two-Channel Photometer has an uncooled RCA 8850 photomultiplier as its primary channel, with an uncooled RCA 4516 photomultiplier as its secondary channel. The instrument is described in Binzel and Mulholland (1983). Binzel, R.P. and J.D. Mulholland, Photometry of Pluto during the 1982 opposition, Astron. J. 88, 222-225, 1983.