Skill: Starship Perception

Starship Perception is a term used to refer to three closely related things in Star Trek Online: This article primarily covers the former two, as the latter is a simple modifier of it.
 * A statistic that determines the distance at which you can detect cloaked starships, countered by the Starship Stealth skill.
 * A Science skill that is part of the equation for the statistic. Like other skills on the skill tree, it is numeric, and boosted by things such as Auxiliary Power and certain items, but that is not available directly from the skill tree.
 * A Science skill unlock available from the skill system.

Overview
Before the various Perception stats can be covered, first one must understand the Stealth Detection Rating.

Each starship has a base Stealth Detection Rating, or SDR (see below). Your starship's Auxiliary Power has an effect on this: every point of power above 50 into the Auxiliary systems will increase your base SDR by 2%. In addition, some items and abilities grant "Starship Stealth Detection", also known as "StealthSight", which also adds significantly to your total SDR: a 2.5% boost to Starship Stealth Detection adds 250 Stealth Detection Rating.

The Starship Perception skill unlock, a choice after spending 15 points on Science skills, doubles the benefit to SDR that you gain from Auxiliary Power, making every point of power above 50 increase your base SDR by 4%. However, while it is called "Starship Perception", it does not increase what is known as the "Perception" stat directly, which is the focus of this article, only your ship's innate Stealth Detection Rating.

To recap, your Stealth Detection Rating can be expressed by the following equation:
 * , or
 * with the skill unlock.

A cloaked ship has a Stealth value, and the distance at which other ships can see the cloaked ship is determined by Perception. Perception is boosted by some items directly (see below), and is derived from SDR with the equation:

The distance at which a cloaked starship can be detected follows the equation:
 * , i.e. 1 km per 50 points of Perception

All together the equation is:

or, with the skill unlock:

For example, if a cloaking device gives an enemy starship 5000 Stealth, and you are in a Science Vessel (Base SDR of 60) with 125 Auxiliary Power, plus an item that grants +20 Perception but no StealthSight, then you will be able to see them at a distance of:

For another example, consider the same situation but with both the skill unlock and an item that adds 2.5% Starship Stealth Detection, such as the Jem'Hadar Deflector Dish:

Affected abilities

 * : +20 Perception, +3.8% StealthSight (0.4 + 4.8 = 5.2km)
 * : +20 Perception, +15% StealthSight for you and up to 10 allies in a 10km sphere
 * : increases Debuff of target's Stealth strength
 * : increases Debuff of target's Stealth strength

Modifiers
Add one or more of these items or abilities to increase your Starship Perception:

Starship type
Each ship has a base Stealth Detection Rating that's determined by its class, as follows:
 * Cruiser: 20
 * Escort: 20
 * Science Vessel: 60

Abilities
Abilities that boost Perception for you and/or your allies: Abilities that cause the target to lose perception:
 * : up to +250 Perception (5km) for 30 sec, plus the added Perception from the Auxiliary Power boost
 * : up to +500 Perception (10km) for 15 sec
 * : -_____ Perception for 16 sec
 * : Decreases StealthSight by 9.99% for 3 sec
 * -X Perception to foes within 2.2km of the anomaly
 * : Creates a Subspace Rupture for 10 sec. To all enemies within 3km of the Rupture: -99.9% Perception
 * : Ejects Theta Radiation Cloud,    -4,720 Perception to anyone caught in it.

Duty officers

 * Conn Officer, Accuracy/Perception variant: 5%-20% chance to boost Perception by 100 for 10 sec when activating Tactical Team. It can stack 3 times for a chance to add +300 Perception (6km)
 * Entertainer, Perception variant: On activation of beams or cannons, provides a 1% chance to reduce target's Perception distance to 20% of current for 6 seconds.
 * Maintenance Engineer, Battery variant: Increases Perception by 10 for 20 sec when using an Auxiliary Battery.

Consoles

 * Console - Science - Sensor Probes: up to +39.4 Perception at Mk XV Epic (0.788km)
 * Console - Science - Exotic Particle Field Exciter with [Per] modifier: up to +39.4 Perception at Mk XV Epic
 * Weapon Signature Nullifiers and Amplifiers with [Per] Modifier: +39.4 Perception at Mk XV Epic
 * Console - Science - Shield Refrequencer with [Per] modifier: up to +26.3 Perception at Mk XV Epic (0.526km)
 * Console - Engineering - Conductive RCS Accelerator with [Per] modifier: up to +39.4 Perception at Mk XV Epic
 * Console - Universal - Ionized Gas Sensor: +28.5 Perception (0.57km)
 * Console - Universal - Tachyon Detection Field: +28.5 Perception
 * Console - Universal - Tachyon Detection Grid: +28.5 Perception

Deflectors

 * Neutrino Deflector Array: up to +21.3 Perception at Mk XV (0.426‬km)
 * Elite Fleet Axion Deflector Array: up to +21.3 Perception at Mk XV
 * Jem'Hadar Deflector Dish: +2.5% Starship Stealth Detection (2.5km)
 * Romulan Advanced Prototype Deflector Dish: +2.5% Starship Stealth Detection
 * Several other special Deflector Dishes, see that page for details.

Set bonuses

 * 2pc Braydon Reconnaissance Technologies Set: +20 Perception (0.4km)

Traits

 * : +10 Perception (+15 with Superior Astrophysicist) (0.2km, Superior 0.3km)
 * : +50 Perception per hangar pet, up to 5 max for +250 Perception (1km per pet, 5km at 5 pets)
 * : +100 (+125 at rank 2) to Science Stats (including Perception) for 8 seconds. (2km, 2.5km at rank 2)