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How to calculate the size of a raster?
Two, as used in the equation above, doubles the resolution. Then that number is multiplied by 1000 to get the map scale. Here’s an example. Say you have a raster with a resolution of 30 meters. Each pixel is 30 meters on a size (an area of 900 square meters).
How big is a 60 meter resolution map?
Each pixel is 30 meters on a size (an area of 900 square meters). You double that to get four pixels (two rows and two columns) with a resolution of 60 meters on a size (an area of 3600 square meters). Then you multiply that 60 meter resolution by 1000 to get a map scale of 60,000.
What is the appropriate resolution for a map scale?
So here is the appropriate resolution for a select set of map scales: For example, if you were not sure what resolution imagery you needed to acquire to detect features at a map scale of 1:50,000, using Tobler’s rule above, you can determine that imagery of approximately 25m [50000/ (1000*2)] resolution would be sufficient.
What does the spatial resolution of a raster mean?
Displaying the raster’s spatial resolution. The spatial resolution of a raster refers to the size of the cells in a raster dataset and the ratio of screen pixels to image pixels at the current map scale.
How many raster cells does a screen display?
In this case, every screen pixel has to display nine raster cells, meaning the image is not as clear and detailed. A resolution of 1:1, however, means that every screen pixel is displaying only one raster cell. If you zoom in closer than a raster resolution of 1:1, you won’t see more detail in that image.
What makes a zone in a raster dataset?
Some raster datasets contain only a few zones, while others contain many. Each group of connected cells in a zone is considered a region. A zone that consists of a single group of connected cells has only one region.
How are assemblages of entities represented in a raster?
Assemblages of entities, such as forest stands in a state, soil types in a county, or single-family houses in a town, are features of an area that will most likely be represented by zones made up of many disconnected groups of connected cells (regions). Every cell in a raster belongs to a zone.
How are raster and feature data used in minority statistics?
For majority and minority statistics, when there is a tie, the output for the zone is based on the lowest of the tied values. The input that defines the zones. Both raster and feature data can be used for the zone input. The field that defines each zone. It can be an integer or a string field of the zone dataset.