Layer files define how your data is displayed. A layer is created by default when you add your raster dataset, raster catalog, or mosaic dataset to ArcMap, ArcGlobe, or ArcScene. When you alter the display properties on the layer's Properties dialog box, you can adjust many different properties, such as the symbology and some display properties such as resampling and transparency, the visible extent, or the visible scale. By saving a layer file for a raster dataset, raster catalog, or mosaic dataset, you can save the layer properties you set when displaying a particular raster. For example:
- You can save the renderer used on the raster dataset layer so you can display the raster the same way at another time.
- You can save a mosaic dataset layer to preserve the mosaic method and transmission compression settings.
- You can save a raster catalog layer to keep specific rendering parameters and settings so the raster catalog displays as a time series.
You can also save a group layer that contains raster datasets or raster catalogs. For example, you can have a group layer that contains basemap information combined with a raster dataset displaying elevation level, with transparency set to allow another raster to show through, such as an orthophotograph. You can save this group layer with all the layer properties to use in another map.
You can save layers within the ArcGIS Desktop applications or using geoprocessing tools. To save a layer within ArcCatalog or the Catalog window, see Saving a raster layer file in ArcCatalog. To save a layer within the other applications, see Saving a raster layer file in ArcMap, ArcScene, or ArcGlobe. There are several geoprocessing tools to assist you in creating layers. The layers created by the tools are temporary and will not persist after the ArcGIS Desktop application session ends unless the document is saved. These tools are as follows:
- Make Raster Layer—Creates a temporary raster dataset layer
- Make Mosiac Layer—Creates a temporary mosaic dataset layer
- Make Raster Catalog Layer—Creates a temporary raster catalog layer
- Make Image Server Layer—Creates a temporary raster layer from an image service
- Make WCS Layer—Creates a temporary raster layer from a WCS service