The galaxy population in the Fornax cluster is well studied down to a B magnitude of 19 mag by the photographic survey of Ferguson (1989) which resulted in the Fornax Cluster Catalog (FCC). In addition, Davies et al. (1988) and Irwin et al. (1990) provided a catalog of the (very) low surface brightness galaxies in this region, which then also have been studied by follow-up CCD photometry (Bothun et al. 1991; Cellone et al. 1996).
The photographic data of Ferguson (1989) were obtained on
the same telescope
as the present study. In Ferguson's survey a diameter limit of 
was
chosen to reduce the number of background galaxies. In our CCD survey
galaxies with smaller scale lengths were included in order to search for
compact dwarf galaxies, e.g. similar to M 32, and to extend the galaxy counts
to fainter absolute magnitudes. Furthermore, CCD photometry provides the
possibility to search for objects in the
immediate environment of giant galaxies (where the galaxy light dominates) when
adopting appropriate reduction techniques.
Our main goal is to find dwarf galaxies in the vicinity of giant ellipticals in the Fornax cluster, especially the central galaxy NGC 1399. One striking characteristic of NGC 1399 (and other central galaxies in clusters) is its extraordinarily rich globular cluster system (GCS), whose origin is a matter of lively debate. Several authors investigated photometric and spectroscopic properties of the GCS (e.g. Hanes & Harris 1986; Bridges et al. 1991; Wagner et al. 1991; Grillmair et al. 1994; Kissler-Patig et al. 1997, 1998a,b; Forbes et al. 1998). Further, NGC 1399 possesses an extended cD halo (Schombert 1986; Killeen & Bicknell 1988), which seems to be typical for the brightest cluster galaxies of dynamically evolved clusters (López-Cruz et al. 1997). The building-up of such a rich GCS as well as the formation of a cD halo are not well understood. Both properties might be related to the infall of dwarf galaxies in the cluster center. A more detailed discussion on this topic will be given in Paper III of this series (Hilker et al. 1998).
In the present paper the photometric properties of all galaxies found in the observed fields are cataloged. The identification, classification and the photometry of the objects as well as the completeness of our counts are described. Furthermore, we present the spatial and the color distribution of the galaxies as well as the surface brightness profile parameters of a subsample of galaxies with a sufficient resolution in their angular diameters. In this paper we adopt a distance to the Fornax cluster of 18.2 Mpc or (m-M)0 = 31.3 mag (Kohle et al. 1996, recalibrated with new distances of Galactic GCs, Gratton et al. 1997, following Della Valle et al. 1998). The spectroscopy and the determination of radial velocities of the brightest galaxies in our sample represents the topic of a second paper (Hilker et al. 1998, hereafter Paper II).
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