Four-color and Hbeta photometry of open clusters. XII. NGC 6910 and NGC 6913.

Intermediate-band photoelectric photometry was obtained for 23 stars in NOC 6910 and 25 in NGC 6913 (M29). By analysis of the data, we conclude that 16 stars are members of the cluster NGC 6910 and 17 of NGC 6913. The average reddening of cluster members is high, about E (b -y )=0.75 mag for both. By using a calibration of P vs My, we fmd a distance modulus of 10.5 mag for NGC 6910 and 10.2 mag for NOC 6913. Neither cluster is rich in members, but both certainly appear real. For NOC 6913, the distance modulus from the photometry does not agree well with that found by use of MK spectra; the agreement is good for NGC 6910. The brightest star in NGC 6910 is an Ia supergiant with absolute magnitude My = -6.9.