After adding the HoloPlayCapture to the scene and selecting it, you can find the settings on the right hand side in the details panel. The main settings here you'll want to keep in mind are Size and FOV.
Editing the Size variable changes the size of the HoloPlay Capture Actor, this is useful when you want to change the scale at which the HoloPlay Capture Actor can focus on.
Editing the field of view changes the amount of the scene visible by the HoloPlay Capture Actor. Note, however, that the default of 14 degrees is intended to ensure that the scene's parallax closely matches real-world parallax. Changing the field of view doesn't break the effect, but it does add some distortion.