Select the "Region" mode and draw a region wherever you want. Use Click and Drag to add new regions. Ctrl + Drag on the region border enables ''Fuzzy" region mode, in which the regions are seamlessly blended into the rest of the image.
By holding your mouse over the Region button you can also toggle all regions on and off, and remove all existing regions.
Column
width
5%
Column
width
50%
...
Section
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45%
To set the Depth of Field focus point from Active (docked) Viewport - start Interactive Rendering in Active Viewport. Then select the object Picker from the Camera Focus Object. Then left-click on an object in your rendering to set the object to focus. This snaps the current camera’s focus point exactly to the selected object.