For Local or Global Focus Surfaces you need to select the focus strategy Use Z-Values/Focus Surface defined in Tiles Setup. This strategy is selected by default, if you have licensed the Tiles & Positions module. Then you can acquire tiles images along local or global focus surfaces (tile region specific/position specific) and use the focus strategy for optimal image results.

A local/global focus surface ensures that all tiles are in focus on tilted or irregular specimens. Local focus surfaces for tile regions are interpolated on the basis of the focus positions of support points. Positions automatically have a horizontal focus area with the Z-value of the position.

The following guide explains how to use the focus strategy for local focus surfaces.

  1. To use the Use Z-Values/Focus Surface defined in Tiles Setup focus strategy, you need a license for the Tiles & Positions module.
  2. You have read the introduction for using focus strategies (experiment created, at least one channel defined, acquisition dimensions activated), see Introduction.
  3. You are on the Acquisition tab in the Focus Strategy tool.
  1. Select the Use Z-Values/Focus Surface defined in Tiles Setup entry from the drop-down list (if not selected by default).
  2. If you want to set up the entire focus strategy, you can click Optimize this Focus Strategy to use the Focus Strategy wizard, see Focus Strategy Wizard.
  3. In the Z-Values/Focus Surface section, select Local (per Region/Position).
  4. Under Initial Definition for Z-Values/Focus Surface, select the By Tiles Setup entry from the drop-down list.
  5. Alternatively, select the options By Software Autofocus or By Definite Focus: Recall Focus if you have licensed the Software Autofocus module and/or use Definite Focus.2 hardware device. This allows you to specify that the z-positions of the support points should be updated by the software autofocus and/or Definite Focus.2 immediately before acquisition.
  6. Set up a Tiles experiment.
  7. Create a local focus surface for the tile regions.
  8. To start the experiment, click Start Experiment.
  1. The tiles of tile regions and positions are acquired using the local focus surfaces.
  2. If you are performing a Time Series experiment, we recommend to use the Adapt Z-Values/Focus Surface functions. By these you can correct the focus for small drifts that occur in long multidimensional time series experiments with living cells, for example.