The Scale of Reddening for Classical Cepheid Variables
  Field reddenings are summarized for 68 Cepheids from published studies and
updated results presented here. The compilation forms the basis for a
comparison with other published reddening scales of Cepheids, including those
established from reddening-independent indices, photometry on the Lick
six-color system, Str\"{o}mgren system, Walraven system, Washington system,
Cape $BVI$ system, DDO system, and Geneva system, IRSB studies, and Cepheid
spectroscopy, both old and new. Reddenings tied to period-color relations are
the least reliable, as expected, while photometric color excesses vary in
precision, their accuracy depending on the methodology and calibration sample.
The tests provide insights into the accuracy and precision of published Cepheid
reddening scales, and lead to a new system of standardized reddenings
comprising a sample of 198 variables with an average uncertainty of $\pm0.028$
in E$_{B-V}$, the precision being less than $\pm0.01$ for many. The collected
color excesses are used to map the dispersion in intrinsic colors as a function
of pulsation period, the results contradicting current perceptions about the
period dependence of dispersion in Cepheid effective temperatures.
