Photometric data has been presented for regions in the vicinity of nine dark nebulae. An appropriate use of such data is for the determination of the distances of the nebulae from the sun. Before such distances can be obtained it is necessary to find the spectral type of each star used in the distance determination.
Acknowledgements
For the granting of telescope time we are grateful to the German-Spanish Astronomical Center, Calar Alto which is operated by the Max Planck Institut fur Astronomie Heidelberg jointly with the Spanish National Commission for Astronomy.