1. To create a local focus surface you need the Tiles & Positions module.
  2. You have set up a Tiles experiment with at least one tile region.
  3. You are on the Acquisition tab in the Tiles tool.
  1. Click Show Viewer.
  2. The advanced tile setup opens.
  3. Select a tile region for which you want to create support points. To do this, click on the corresponding tile region in the list in the Tile Regions section of the Tiles tool. Alternatively, you can select tile regions by clicking directly on the desired tile region in the Advanced Setup view. Both methods allow you to select several tile regions when pressing the Ctrl key.
  4. Open the Focus Surface and Support Points section in the Tiles tool.
  5. To add a single support point at the current stage position, click Current Position. Alternatively, you can add a single support point to the center of the currently selected tile region by clicking Center of Tile Region.
  6. Under Add Multiple Support Points, you have the settings to add multiple support points. Indicate the number of Columns and Rows for the distribution of the reference points. Alternatively, recommended for larger tile regions (>200 tiles), you can use the distribution method Onion Skin. Depending on the total size and shape you might need to adjust the density parameter and/ or the maximum number of support points to optimize the result. Typically, this method works best with large irregular or rounded tile regions.
  7. Click Distribute.
  8. The support points are distributed within the selected tile region(s) and shown as yellow points in the stage view.
  9. The support points of the selected tile region are displayed with their coordinates in the Local (per Tile Region) list in the Focus Surface and Support Points section of the Tiles tool.
  10. If necessary, you can adjust the distribution of the support points manually in the Tiles - Advanced Setup. You can change the position of the support points using drag & drop.
  11. Repeat the steps until you have distributed reference points across all desired tile regions.
  1. You have successfully distributed support points across the tile regions.

Automatic Distribution

If you activate Auto-Distribute for New Tile Regions in the Focus Surface and Support Points Section of the Tiles tool, support points are automatically added and distributed for all newly created tile regions.

Support Point Distribution

Distribute the support points evenly across your tile region. The more irregular the surface of your specimen, the more reference points you should set. An even but tilted surface requires at least 4 reference points for a solid calculation, while a simple saddle surface requires at least 9 reference points. A high reference point density leads to a more precise result, although the maximum useful density is one reference point per tile. The generic method follows a simple grid pattern to place the support points. It works well on regular rectangular tile regions smaller in size. For larger (>200 tiles) tile regions the Onion Skin will likely provide better results. In some cases, trial and error might be needed to optimize the parameters.