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Many emission features in the spectra of Early Carbon Wolf-Rayet stars (Subtypes WC4-WC7, hereafter WCE) show little change in strength between different stars, in contrast to the strong variation of line strengths seen in the classification lines of these stars. These small variation emission lines can be used as standard candles to estimate magnitudes and distances for single WC stars. Using 13 single WC stars with known distances, an average flux value is computed for 54 different emission features. These standard emission line values are then used to compute magnitudes and distances for 35 Galactic and LMC single WC stars.
Furthermore, magnitude differences in binary or composite WC+OB systems can be determined by comparing the equivalent widths (EW) of the small variation lines with those of single WC stars. By assuming the flux of an emission line comes only from the WC star, a simple formula involving ratios of EW's leads directly to the magnitude difference between the WC star and it's companion. Magnitude differences are computed for 27 Galactic and LMC WC+OB systems. Absolute magnitudes are reported for all 35 single WC stars and those WC+OB systems with known distances.
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