Comparison of effective temperatures (upper left), gravity (upper right), log Q (lower left) and Y_He (lower right) obtained from the optical spectra with the different clumping laws considered in this work. The abscissa gives the identification number of the star. For each star, the results from the different clumping laws (including the smooth wind model) are plotted (see legend). Corresponding entries (except for the smooth wind results) have been slightly displaced on the abscissa. Stars are ordered as in Table 1: #1: HD 46223; #2: HD 15629; #3: HD 46150; #4: HD 217086; #5: HD 149757; #6: HD 190864; #7: HD 203064; #8: HD 15570; #9: HD 14947; #10: HD30614; #11: HD 210809; #12: HD 209975. Rapid rotators are stars #4, #5, and #7.