1 Introduction

Continuing a series of papers on dwarf galaxies within 10 Mpc (Bremnes et al. 1998; Lesaffre et al. 1999; Bremnes et al. 1999), hereafter Papers I, II and III, we here present photometric data on dwarf galaxies in the Canes Venatici I cloud (CVnI). The cloud is composed of some 40 galaxies distributed in the region of the sky delimited by $11\hbox{$.\!\!^{\rm h}$ }5 <\alpha< 14\hbox{$.\!\!^{\rm h}$ }0$, $+20\hbox{$^\circ$ }<\delta< +60\hbox{$^\circ$ }$(Makarova et al. 1998) and has a mean heliocentric radial velocity of $\mathopen{<}v_{\mathrm{hel}}\mathclose{>} \approx$ 300 km s^-1. A map showing the distribution of these objects on the sky is shown by Makarova et al.  (1998) in their Fig. 1. The structure of the cloud is somewhat different from the groups studied in Papers I, II and III in that there is no dominant galaxy, like in the M 81 or M 101 groups. It is constituted of several loose aggregations of galaxies, mostly of late types. This study therefore complements Papers I, II and III towards globally lower density environments. Accurate distances are becoming available as photometric distance determinations (Makarova et al. 1997; Georgiev et al. 1997; Tikhonov & Karachentsev 1998; Makarova et al. 1998; Karachentsev & Drozdovsky 1998). The combination of distance information and photometry will enable a thorough study of the photometric parameters of these systems.

In the following section we describe the sample and the imaging, in Sect. 3 we describe the reduction procedure. The results are presented in Sect. 4. Model-free parameters, i.e. total magnitudes, effective radii and effective surface brightnesses were determined in the Cousins B and R bands. Best fitting exponential model parameters, i.e. extrapolated central surface brightness and exponential scale length were also determined. Finally, color gradients were measured for all but two galaxies lacking images in both colors. The tables and profile data in electronic format are available from us on request.