Adding data from ISAT to a mosaic dataset

Available with Standard or Advanced license.

ImageStation Automatic Triangulation (ISAT) is an automatic image point extraction and triangulation package from Intergraph. Both analog and digital cameras are supported. The input file used by this raster type is the ISAT project file.

ISAT data can be added to a mosaic dataset using the ISAT raster type.

1. Create a mosaic dataset.
2. Right-click the mosaic dataset in the Catalog window or ArcCatalog and click Add Rasters.

   The Add Rasters To Mosaic Dataset dialog box opens.

3. Click the Raster Type drop-down list and click ISAT.
4. Click the Edit Raster Type Properties button .

   The Raster Type Properties dialog box is opened. Here you will enter specific information about the DEM and camera.

5. Click the Properties tab.

   This tab allows you to specify the properties that will define the elevation model used in the orthorectification of the imagery.

   Tip:

   Make sure the spatial reference system in the exterior orientation file and the DEM are the same; otherwise, you may have to modify the DEM by either checking the Geoid check box or entering z offset and factor values.

6. Click the Orthorectification using elevation radio button to choose one of the methods:

   Average elevation	When using the ISAT raster type, the average elevation is read from the project file.
   Constant elevation	Enter the value of the constant (average) elevation for the area covered by the images.
   DEM	Choose the DEM from a raster dataset, mosaic dataset, image service, or WCS service you want to use for orthorectification.

   If you need to apply a geoid correction to your elevation data you should create a mosaic dataset containing the elevation data and use the Arithmetic function to apply the required equation. For specific steps, see Converting from orthometric to ellipsoidal heights.

7. Optionally, you may need to set the Elevation adjustment parameters.

   Z offset	The base value to be added to the elevation value in the DEM. This could be used to offset elevation values that do not start at sea level.
   Z factor	The z-factor is a scaling factor used to convert the elevation values for two purposes: To convert the elevation units (such as meters or feet) to the horizontal coordinate units of the dataset, which may be feet, meters, or degrees. To add vertical exaggeration for visual effect.

8. Click the Auxiliary Inputs tab.
9. Click the Photo File browse button and navigate to the ISAT photo file.
10. Click the Camera File browse button and navigate to the ISAT camera file.
11. Click OK.
12. Optionally, click the General tab.

    By clicking the Save As button, you can save the changes made to the raster type so it can be reused at another time.

    To use the .art file you save, you can browse to it rather than choosing ISAT in the Raster Type list.

13. Click OK.
14. Click the Input drop-down arrow and click File.
15. Click the browse button , navigate to the ISAT project file, then click Open.

    The text file is added to the Source list.

16. Optionally, click the General tab.

    By clicking the Save As button, you can save the changes made to the raster type so it can be reused at another time.

    To use the .art file you save, you can browse to it rather than choosing ISAT in the Raster Type list.

17. Optionally, if you won't be recalculating the footprints, you can check Update Overviews.

    You might want to shrink the footprints. If so, don't check Update Overviews; complete running this tool. Use the Build Footprints tool and specify a value for Shrink Distance. (Also, change the maximum and minimum data values to the highs and lows of the bit depth, such as 0 and 255 for 8-bit data). Finally, you can build overviews using the Build Overviews tool.

18. There may be some additional details you need to define within the Advanced Options section, although they are not always necessary. For example:
    1. If the spatial reference for the input data is different from the mosaic dataset, you will need to define one with the Coordinate system for Input Data parameter.
    2. If the data does not have pyramids or statistics, you calculate them by checking Build Raster Pyramids and Calculate Statistics.
19. Click OK to run the tool and add the data to the mosaic dataset.

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