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Seven-color photometry in the Vilnius system has been obtained for 420 stars down to V=16 mag in the area containing the overlapping open clusters NGC 1750 and NGC 1758 in Taurus. Spectral and luminosity classes, color excesses, interstellar extinctions, and interstellar distances are given for 287 stars. The classification of stars is based on their reddening-free Q-parameters. Eighteen stars observed photoelectrically were used as standards. The extinction versus distance diagram exhibits the presence of one dust cloud at a distance of 175 pc, which almost coincides with the distance of other dust clouds in the Taurus complex. The clusters NGC 1750 and NGC 1758 are found to be at the same distance of approximately 760 pc and may penetrate each other. Their interstellar extinction A(V) is 1.06 mag, which corresponds to E(B-V) = 0.34 mag. (3 tables, 5 figures, 10 refs.)

Spectral and luminosity classes, absolute magnitudes, color excesses, interstellar extinctions and distances are determined for 98 stars down to 18 mag in the Barnard 1 dark cloud belonging to the Per OB2 association. The classification of stars is based on their photoelectric photometry in the Vilnius seven-color photometric system. The extinction vs. distance diagram exhibits the presence of two dust layers at 150 and 230 pc distances. The distance of the first cloud, which gives an extinction Ay of 0.3 mag, coincides with the distance of the Taurus dark cloud complex. The second cloud with much larger extinction is about at the same distance as the clouds in the direction of the nearby objects: reflection nebula NGC 1333 and open cluster IG 348.