Note: If you cannot fit all your content into areas 2, 3, and 4, thats alright. We recommend using Unity's Post-Processing Effects Depth Of Field to assist smoothing content that reaches into areas 1 and 5.
Within The Frustum
To get the most depth in your app, we suggest the following guides.
Use the Leia Camera's Baseline Scaling to change the frustum so the near and far planes of the frustum closely capture all your objects
Ensure the Leia Camera's Convergence Distance sits on or close to your primary focus
Assets from Unity Learn: 3D Game Kit Lite
In this example, the scene has been setup so that..
All content fits snug in the Frustum bounds, maximizing depth
Objects we want to pop out of the screen are in front of the convergence plane
Objects we want to recess into the screen are behind the convergence plane
The main character pops outside the screen and the creatures recess inward. Great!
Baseline Scaling - Ensuring that Snug Fit
You may think 'Ahh, but if I lower the Baseline Scaling value, I will easily fit all my content into the Frustum.'
While yes, your content will easily fit in the Frustum, you also reduce the amount of depth.
With the Baseline Scaling reduced beyond necessity, the depth queues are diminished. Here is the result of the above settings. Note that depth is much less noticeable than the above example.
We recommend experimenting with the Baseline Scaling and Convergence Distance to maximize your depth experience.