Focused Mage Sight allows a mage to scrutinize a subject through the lens of the chosen Arcana. Unlike Peripheral or Active Mage Sight, Focused Mage Sight requires that the mage put all her attention on one target — a person, object, or location (roughly the size of a small room).
Instead of seeing the subject in the context of the Supernal, she sees the Supernal as filtered through the subject. Magic pours through the subject, shaped by its Fallen World constraints and correspondences; and by examining that interaction, the mage can learn much about it.
Using this principle, a mage can release Mana into the world and watch the Patterns it forms, gleaning additional information from them.
Focused Mage Sight has its dangers, however. Looking so deeply into the Supernal isn’t a passive, casual observation. The mage is undertaking the magical equivalent of a thorough, persistent, and even invasive investigation, pouring magical energy into the area, and anything with the ability to sense magic (including other mages in the area) can notice this.
Otherworldly beings might observe her inquiry, and some of them would prefer to remain unseen.
A mage must be using Active Mage Sight already to Focus. Focused Mage Sight has two stages: Scrutiny and Revelation. Both pit the perceptive power of the mage against the complexity of the Mystery she is trying to illuminate.
This is represented in game terms by a trait called Opacity — simply put, an abstract measure of how deep a mage must delve in order to fully understand a Mystery.
A mage can attempt Revelation at any time. Revelation is the magical equivalent of a glance, a summary, a quick-read through, or a taste test. On its own, it can be useful, even illuminating, but it does not grant the mage depth of knowledge.
For that, she needs Scrutiny, the in-depth, time-consuming, and sometimes dangerous practice of magically studying a target.
Revelation and Scrutiny are two different actions. They can be attempted in either order; a mage can Reveal a Mystery before Scrutinizing it to gain a baseline understanding, or Scrutinize the Mystery before Revealing it to reduce its Opacity.
What a mage cannot do, however, is Reveal a Mystery twice without Scrutinizing it. Once a mage has Revealed a Mystery, she has learned all she can without using Scrutiny.