Editing derived tiles

步骤：

1. Open the service table.
2. Select a derived tile that you want to edit. You can either close the service table or minimize it.
3. Click the Image Service drop-down menu on the Image Service Definition Editor toolbar and click Advanced > Optimize > Derived Tiles > Edit.
4. Move the handles or anchor points to change the shape and size of the derived tile.
5. Click the Image Service drop-down menu and click Advanced > Optimize > Derived Tiles > Edit to save your changes.