Highlight Boxes added to a Captivate project provide an excellent way to direct a learner's attention to a specific area of a published eLearning lesson.
If you have spent any time in Captivate, you have likely added at least one Highlight Box to a project. If you haven't, you'll find that you can add them easily enough via Insert > Standard Object > Highlight Box.
After the Highlight Box appears on the slide, you can drag it to a desired location and resize it appropriately. You would then use the Timeline to control when the Highlight Box appears on the slide. Assuming you haven't made the Fill Transparency too high or too low (20% is typical), when a learner watches your published lesson, the area within the Highlight Box will darken just enough to command the learner's attention. As the middle of the highlighted area gets darker, the rest of the slide remains unchanged.
There is a Highlight Box feature you may not have realized is available: a Reverse Highlight Box. When inserting a Highlight Box, there is an innocent-looking option at the bottom of the Fill & Stroke group of the Properties panel: Fill Outer Area.
If you enable Fill Outer Area and raise the Fill Alpha (in the picture above, the value has been raised to 80), the Highlight Box will actually block everything outside the Highlight Box area (basically the reverse behavior of a typical Highlight Box).
While not appropriate for every situation, Highlight Boxes with filled outer areas are ideal if the interface you are discussing is cluttered. And you certainly don't have to raise the Fill Alpha all the way to 80. Instead, you can experiment with a value that works best for you.
Note: If you'd like to see a reverse highlight box in action, check out this video demonstration on our YouTube channel.
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