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ArcGIS Tips and Tricks

General

• Be sure to save your map document frequently
• Work off the C: local drive for faster performance, then copy your working directory to your flash drive at the end of your session. If you have trouble managing your files among the different drives, then just work with files either on the server or flash drive.
• Remember to set Relative Paths in the Document Properties.
• Whenever you are prompted to specify output names for feature classes, tables, etc. do not just accept the default file path and name. Be sure that the output path is pointing to the appropriate drive letter and folder (e.g., C:/Workspace/clark/lab6". Give your output layers appropriate names that you will be able to understand later.
  For example, "Export_Output.shp" is NOT a useful layer name, while "USA_Counties_Alber_Nad83.shp" is useful... we know the feature content and projection just by reading the name.
• You may encounter problems dragging layers from ArcCatalog to ArcMap, giving you a "read/write" lock problem. This is a typical problem with ArcCatalog and ArcMap not sharing layers properly between the two modules. To get around this problem, close the module that you don't need. For example, close ArcCatalog if you want to work primarily in ArcMap.
• You can tell ArcMap to overwrite previous versions of your feature classes or rasters by going under Tools...Options, then Geoprocessing tab. Click the box "Overwrite the outputs of geoprocessing operations". This way you don't have to make a new version of a feature class/raster when you make a mistake the first time. When using an ArcTool and when selecting an exisiting feature class/raster as output, you will see a yellow exclamation mark. If you didn't have the "Overwrite" option turned on, then you would see a red X mark, and the geoprocessing tool will bail out with an error.
• If you copy or "unzip" files to a directory after you have opened ArcCatalog, then you may need to "refresh" the table of contents in ArcCatalog to see your data. You can do this quickly with the F5 shortcut key. Just click the directory that you want to refresh and press the F5 key on your keyboard.

Digitization

• When digitizing be sure to SAVE EDITS regularly... preferably after you digitize and attribute each polygon!
• When digitizing, if your snapping does not occur until you get very close to your previously digitized polygon, then you may have to modify your SNAPPING TOLERANCE. This can be done in the Editor Toolbar. Go under the Editor drop-down menu and select Options... In the General tab you can modify the snapping tolerance. You can use either pixel distances or map units (e.g., feet in this lab) with the pop-up menu to the right of the value window. Try experimenting with different values (e.g., 5 feet).