You are using a raster symbology option that calculates the stretch statistics from the pixels in the current display extent rather than the entire raster dataset. Each time the display extent (or location) changes, the raster dataset will potentially be displayed in a different way, because the contrast stretch calculated for the cell values in the display will potentially change. This setting requires recalculation of image statistics each time the raster dataset is redrawn and can result in severely degraded performance.
This option is not supported in basemap layers and map services.
Select another method of calculating statistics for your raster dataset or raster catalog, such as From Each Raster Dataset or From Custom Settings.
The Stretched symbology option displays continuous raster cell values across a gradual ramp of colors. Use the Stretched symbology option when you want to draw a single band of continuous data. It works well when you have a large range of values that you want to display, such as in spectral imagery, aerial photographs, or elevation models.
See the geoprocessing tool Calculate Statistics for more information on how to perform this operation.