The application and analysis that is to be performed.The spatial resolution of the input data.The following factors should be considered when specifying the cell size: This could increase your analysis processing speed. Depending on your future plans for your data, it may be worthwhile to store a copy of your data at its smallest and most accurate cell size, meanwhile resampling it to match that of your largest and least accurate. A raster dataset can always be resampled to have a larger cell size however, you will not obtain any greater detail by resampling your raster to have a smaller cell size. Comparing spatial resolution to information content.ĭetermining an adequate cell size is just as important in your GIS application planning stages as determining what datasets to obtain. The more homogeneous an area is for critical variables, such as topography and land use, the larger the cell size can be without affecting accuracy. If you're using a classified dataset derived from 30-meter resolution Landsat imagery, then creating a digital elevation model (DEM) or other ancillary data at a higher resolution, such as 10 meters, may be unnecessary. Essentially, in a GIS, your results will only be as accurate as your least accurate dataset. You must balance your application's need for spatial resolution with practical requirements for quick display, processing time, and storage. Learn about displaying the raster's spatial resolution in ArcMapĬhoosing an appropriate cell size is not always simple.Smaller cell sizes result in larger raster datasets to represent an entire surface therefore, there is a need for greater storage space, which often results in longer processing time. More features, smaller features, or a greater detail in the extents of features can be represented by a raster with a smaller cell size. The cell must be small enough to capture the required detail but large enough so computer storage and analysis can be performed efficiently.
The level of detail (of features/phenomena) represented by a raster is often dependent on the cell (pixel) size, or spatial resolution, of the raster.
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