Introduction

Dwarf galaxies, as their name suggests, are small galaxies. In addition to being small, they also sport a low [central] surface brightness, which decreases with decreasing total luminosity, as opposed to ``normal'' galaxies, where fainter galaxies show higher central surface brightnesses. The aforementioned properties make the discovery and subsequent detailed analysis of these objects difficult: the objects are mostly barely visible on photographic plates (e.g. POSS plates), and their distances are often unknown, as these systems are often almost devoid of HI gas ². See Figs.  and for a comparison among typical giant and dwarf galaxies, and fig.  for a sketch of the central surface brightness vs. absolute magnitude parameter relation. Note the scale length of the images. Being probably the most numerous galaxies in the universe,they are supposed to hold important clues as to the formation and evolution of all galaxies. Despite their relative importance we only have sparse knowledge on these objects, especially at larger distances. But to understand objects far away it is important to know those in our neigbourhood well. To that effect one needs a preferably complete sample of galaxies. One such sample is represented by the Kraan-Korteweg & Tammann (1979) 10Mpc catalog of objects within 10Mpc from the Milky Way. This catalogue has been supplemented by numerous newly discovered faint objects, some of these with good distances. To date this sample contains approx. 300 galaxies, and can be called the only 'fair sample' of the universe. Such a sample is crucial for the determination of the faint end of the Luminosity function (LF), which for example is important in the context of cosmological studies.This work is part of a long term project aimed at determining basic photometric parameters of all galaxies within the 10Mpc volume using CCD imaging with medium sized³ telescopes⁴. Until now⁵around 100 galaxies have been imaged using the 1.2 meter telescope at the Observatoire de haute Provence (OHP). From these galaxies global photometric properties were determined and preliminary statistical investigations made.

Figure: NGC2997 and M87 (images are 2#2kpc on a side)

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Figure: dE, Im and Im/BCD (images are 6#6, 7#7, and 8#8kpc on a side)

[dE] 3#3[Im] 4#4[Im/BCD] 5#5

Figure: Schematic surface brightness versus luminosity diagram.

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