DDO PHOTOMETRY OF E-REGION STARS AND EQUATORIAL STANDARDS .2.

This paper deals with the observations of 72 of McClure's equatorial s tandard stars, made with the same photometer and DDO filters as were u sed for the E-region stars in Cousins' Paper I in order to standardize the observations. These observations were reduced in the natural syst em and later transformed into McClure's system. Zero-point ties betwee n the equatorial and E-region stars were also needed to standardize th e latter system. With the exception of C (38 - 41), our photometry agr ees as well with McClure's standard system as his own observations do, but both show some small, apparently systematic, differences which ar e almost inevitable with a system like the DDO unless the response fun ctions are very well matched. Comparisons with 17 of Dean's measuremen ts of E-region stars show good agreement (similar to 2 mmag) for the a veraged zero-points, but there are small colour differences affecting C (35 - 38) and C (38 - 41) because of differences between the filters and the reduction procedures. This paper also deals with several prob lems in the DDO photometry that have implications for precision photom etry in general.