Both the clusters appear as weak concentrations of a small group of bright stars well mixed with the rich Galactic disk field star population toward their direction. This fact renders it difficult to study these objects, and it is the main reason for which they have been almost neglected up to now.
NGC 1348 has in fact never studied.
On the other hand, NGC 133
(OCL 296, Lund 17, C0028+60, Trumpler class IV 1p:b)
seems to be an asterism of 5 bright stars.
Evidence has been brought forth by
an early photographic study by Jasevicius (1964, 1970)
that this is not a cluster, but simply a random concentration
of a few bright stars.
In this study we would like to address the issue
of the real nature of these two clusters by means
of deep CCD multicolor photometry, and proper motion
data from Tycho 2 catalog.
This study is part of a long term project aimed at providing accurate CCD photometry for northern star clusters at the Asiago Astrophysical Observatory (Carraro 2002, and references therein).
The plan of this paper is as follows.
In Sect. 2 we briefly present the observations and data reduction. Sections 3 to 4 illustrate our results for NGC 133 and NGC 1348, respectively. Finally, Sect. 5 draws some conclusions and suggests further lines of research.
Copyright ESO 2002