Scale and resolution have long been key issues of geography. In recent years, the rapid development of desktop or Internet Geographic Information Systems (GIS) has forced a more precise consideration of these concepts. This research focuses on fitting the resolution of morphologic and thematic raster data, to the scale chosen to represent them in a GIS. To better adapt this resolution, reference aggregation methods based on the type of data are proposed. In the case of morphological raster data, this reference method is visually and statistically compared with two other alternative methods potentially used in existing interfaces. The feasibility of this research's concepts has been tested with an interactive web interface created for this purpose. This work demonstrates that it is necessary to adjust carefully the resolution of raster data to the display scale chosen by the user.