Description
This paper describes the observations and gives the results of a series of observations of bright E-region stars (Cousins A.W.J. and Stoy R.H., 1962RGOB...49....3C) for use as zero point stars for DDO photometry in the southern hemisphere. The list comprises 45 stars, all brighter than V=6.0, and gives the colours in the instrumental system with internal s.e. +/-0.001mag and m_48_ with s.e. +/-0.002mag. The observed m_48_ is indistinguishable from McClure's system and has the same zero point (+/-0.002mag). The individual E-region zero points have been established with s.e. +/-0.001 relative to the instrumental system, but the colour equations (and zero point corrections) to transform the instrumental colours to McClure's system have still to be finalised. For a description of the DDO photometric system, see e.g. <GCPD/12>
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