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Shields: Difference between revisions

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Hirmuolio Pine (talk | contribs)
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Hirmuolio Pine (talk | contribs)
Removed confusing examples, combined the two stackign sections, combined the recharge rate sections. Overlaps with the other shield page
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{{Cleanup|Overlaps with [[Passive Shield Tank]].}}
''This article explains the functional process of spaceship shielding. It does not cover the various tactical applications of shields. These can be found in such as:''
''This article explains the functional process of spaceship shielding. It does not cover the various tactical applications of shields. These can be found in such as:''


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You can think of a shield as a sphere, completely enclosing the ship at a location just inside its [[Signature_radius|Signature Radius]]. [[File:QSG_shield_types.png|right|220px|alt=shield damage types (layers)]] Since the Signature Radius is the effective size of the ship – the area that is targeted by weapons – the shield intercepts any damage that occurs before it can reach the ship. At that point, the damage is filtered – some is rejected and the remainder is passed through to the ship's armor.
You can think of a shield as a sphere, completely enclosing the ship at a location just inside its [[Signature_radius|Signature Radius]]. [[File:QSG_shield_types.png|right|220px|alt=shield damage types (layers)]] Since the Signature Radius is the effective size of the ship – the area that is targeted by weapons – the shield intercepts any damage that occurs before it can reach the ship. At that point, the damage is filtered – some is rejected and the remainder is passed through to the ship's armor.


The shield consists of four separate, overlapping spheres, called "resistance layers", each of which protects against a different kind of damage. This means that the ship has a different shield resistance value for each of: [[Damage_types|thermal, kinetic, EM, and explosive]] damage. <span style="color:#ccffee">Resistance</span> indicates how much of that kind of damage will be rejected by the shield when the ship is hit by that kind of weapon. Resistance values are always shown in percentages – for example, "30% Thermal Resistance" means that the shield will reject 30% of the damage from any weapons hit that does thermal damage.  
The ships shields have a different shield resistance value for each of: [[Damage_types|thermal, kinetic, EM, and explosive]] damage. <span style="color:#ccffee">Resistance</span> indicates how much of that kind of damage will be rejected by the shield when the ship is hit by that kind of weapon. Resistance values are always shown in percentages – for example, "30% Thermal Resistance" means that the shield will reject 30% of the damage from any weapons hit that does thermal damage.  


[[File:QSG_shieldcapacity_dashboard.png|right|350px|alt=heads up display showing shield about half destroyed]]The shield also has a <span style="color:#ccffee">capacity</span> which shows how many hitpoints of damage it would take to destroy, or "drop", the shield. In combat this shows as the outermost of three red rings on the pilot's dashboard display. A ship's shield also has a <span style="color:#ccffee">recharge rate</span> which shows how fast the shield rebuilds itself while damaged.  
[[File:QSG_shieldcapacity_dashboard.png|right|350px|alt=heads up display showing shield about half destroyed]]The shield also has a <span style="color:#ccffee">capacity</span> which shows how many hitpoints of damage it would take to destroy, or "drop", the shield. In combat this shows as the outermost of three red rings on the pilot's dashboard display. A ship's shield also has a <span style="color:#ccffee">recharge rate</span> which shows how fast the shield rebuilds itself while damaged.  
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*Shield Resistance: EM:0% Thermal:20% Kinetic:40% Explosive:50%}}   
*Shield Resistance: EM:0% Thermal:20% Kinetic:40% Explosive:50%}}   


Notice that both ships have the same four shield resistance values. This is because the resistances are expressed in percentages. The Hurricane starts out with almost three times as many hitpoints, thus each percentage absorbs considerably more damage than will the Kestrel. In each case the shield recharge time is an average of what might happen in practice. The actual shield recharge rate varies quite a bit in combat – this is discussed in the [[#Shield Recharge Rate|Shield Recharge Rate]] section, below.
Notice that both ships have the same four shield resistance values. This is because the resistances are expressed in percentages. The Hurricane starts out with almost three times as many hitpoints, thus each percentage absorbs considerably more damage than will the Kestrel. In each case the shield recharge time tells how long it takes for shields to go from empy to 99% capacity. The actual shield recharge rate varies quite a bit in combat – this is discussed in the [[#Shield Recharge Rate|Shield Recharge Rate]] section, below.


===Resistance and Vulnerability===
===Resistance and Vulnerability===


There are four types of damage, and a shield will deal with each differently. As illustrated here, a ship begins with a base Damage Resistance value for each type:
[[File:QSG_hurricane_shield.png|400px|thumb|Base resistances of hurricane battlecruiser. The four resistances shown for this ship show how much of each type of damage the shield will reject.]]


[[File:QSG_hurricane_shield.png|center|400px|alt=shield get info attributes for minmatar hurricane]]
There are four types of damage, and a shield will deal with each separately based on shield resists.


The four resistances shown for this ship show how much of each type of damage the shield will reject. Each of these resistance values also represents a corresponding "vulnerability" number that shows how much damage will ''get through the shield'' for each hit of that kind of weapon. [[File:QSG_shielddefense.gif|left|alt=animation showing damage rejection]]The Vulnerabilities are always 100% minus the resistances. So, for example, a ship with these resistances:
[[File:QSG_shielddefense.gif|260px|thumb|Animation showing damage rejection]]
 
Each of these resistance values also represents a corresponding "vulnerability" number that shows how much damage will ''get through the shield'' for each hit of that kind of weapon. The Vulnerabilities are always 100% minus the resistances. So, for example, a ship with these resistances:


  Shield Resistance: EM:0% Thermal:20% Kinetic:40% Explosive:50%
  Shield Resistance: EM:0% Thermal:20% Kinetic:40% Explosive:50%
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This is the damage that would impact on the shield if the ship flew with no benefits from skills, modules or rigs. ''Because of the way the shield damage reduction modules and rigs work, it is often more useful to focus on the shield's Vulnerabilities than its Resistances.''{{clear}}
This is the damage that would impact on the shield if the ship flew with no benefits from skills, modules or rigs. ''Because of the way the shield damage reduction modules and rigs work, it is often more useful to focus on the shield's Vulnerabilities than its Resistances.''{{clear}}


===Stacking Penalties===
Some of the shield enhancement modules that are discussed in the next few sections are subject to [[Stacking_penalties|Stacking penalties]] which progressively reduce the effectiveness of the modules if they alter the same attribute. In other words, the second module is less than 100% effective, the third even less so, and so on. For shield attributes:
*Penalized: Shield resistances, Shield boost
*Not Penalized: Shield recharge rate, Shield hit points
The penalty only applies to the module's impact on the affected attribute, and progresses as follows:
:1st mod: 100.0% effectiveness
:2nd mod: 86.9% effectiveness
:3rd mod: 57.1% effectiveness
:4th mod: 28.3% effectiveness
:... etc.
The modules are penalized in order from least effective to more effective - the "best" module for that attribute will be the one that works at 100%; the "second best" one at 86.9%.
Consideration of penalties while the choosing the proper equipment for a ship comes under the heading of "[[fitting]]" which is not covered in detail in this article – but stacking more than three modules is generally considered to be a bad idea. For more see the example in the [[#Technical_Section:_Fitting_Multiple_Modules_with_Stacking_Penalties|Technical Section]], below.


===Shield Capacity===
===Shield Capacity===
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*Capacitor Use: no
*Capacitor Use: no
*Applies to damage type(s): all
*Applies to damage type(s): all
}}
===Shield Recharge Rate===
It takes a certain amount of time to recharge a fully depleted shield. This figure is given as the Shield Recharge Time in the ship's Attribute window. Recharging, however, does not tick along like the numbers on a clock. The speed varies depending on the amount of damage the shield has already taken.
[[File:QSG_shieldsimpledrawing2.png|thumb|upright=2.5|left|alt=simplified shield recharge rate graph]]In the beginning, the shield charges at its [[#Technical Section: Shield Recharge Rate|average rate]]. As the shield takes damage, and it's capacity goes '''''down''''', the rate at which it rebuilds itself goes '''''up'''''. If you want, you can think of this as the shield storing energy from the hits that it is taking and feeding the stored energy back into itself.
But then, when the shield capacity has dropped to about 25% (''in other words, when the shield is three-quarters gone''), the recharge rate peaks and begins to fall off. At its peak, the shield will be recharging about twice as fast as it was in the beginning.
At this point a buzzer will sound, to warn the pilot that the shield is at its recharging limit. If it continues to take more damage than it can hold, the recharge rate will drop off quickly, and the capacity of the shield will fall towards zero ... at zero the shield will go down.
The graph shown here is a simplified version of the [[#Technical Section: Shield Recharge Rate|Shield Recharge Rate Graph]]. A ship's shield begins at 100% full capacity ... the left side of the graph. As the shield takes damage, the ''rate at which it recharges'' slowly grows, until, when the shield is at about 25% of its capacity, the rate is more than twice what it was at the start. From then on, if the shield capacity continues to fall, the recharge rate will being to decrease. If damage continues, the shield will soon fail.{{clear}}
{{ note box | THE MAIN POINT: In combat the shield will recharge at an increasing rate until 25% of its capacity remains; then the rate will fall off quickly towards zero.}}
[https://wiki.eveonline.com/en/wiki/Item_Database:Ship_Equipment:Shield:Shield_Flux_Coils Flux Coil], [https://wiki.eveonline.com/en/wiki/Item_Database:Ship_Equipment:Shield:Shield_Power_Relays Power Relay] and [https://wiki.eveonline.com/en/wiki/Item_Database:Ship_Equipment:Shield:Shield_Rechargers Shield Recharger] modules all increase the Recharge Rate of the shield and so decrease the amount of time it takes to rebuild lost shield capacity. [https://wiki.eveonline.com/en/wiki/Medium_Core_Defense_Field_Purger_I Core Defense Field Purger] rigs also increase the shield Recharge Rate, but at the expense of Signature Radius.
{{Example |  Example: [https://wiki.eveonline.com/en/wiki/Basic_Shield_Flux_Coil Basic Shield Flux Coil]
[[File:QSG_fluxcoilI.png|thumb|alt=shield flux coil I get info attributes]]
*Bonus: increases the shield recharge rate by 20%
*Stacking Penalty: no
*Other Penalty: reduces the shield capacity by 10%
*Signature Radius Penalty: no
*Capacitor Use: no
*Applies to damage type: All
}}
}}


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{{sk | Capital Shield Emission Systems }} – 5% reduced capacitor need for capital shield emission system modules per skill level
{{sk | Capital Shield Emission Systems }} – 5% reduced capacitor need for capital shield emission system modules per skill level


==Technical Section: Shield Recharge Rate==
==Shield Recharge Rate==


[[File:Shield_recharge.png|400px|thumb|Measured shield HP during passive recharge from zero and theoretical shield HP from formula plotted. Click to enlarge.]]
[[File:Shield_recharge.png|400px|thumb|Measured shield HP during passive recharge from zero and theoretical shield HP from formula plotted. Click to enlarge.]]
[[File:Shield recharge rate.png|400px|thumb|Shield recharge rate as function of shield HP according to the formula. Click to enlarge.]]


[[File:Shield recharge rate.png|400px|thumb|Shield recharge rate as function of shield HP according to the formula. Click to enlarge.]]
It takes a certain amount of time to recharge a fully depleted shield. This figure is given as the Shield Recharge Time in the ship's Attribute window. Recharging, however, does not tick along like the numbers on a clock. The speed varies depending on how full the shields are.
 
As the shield takes damage, and it's capacity goes '''''down''''', the rate at which it rebuilds itself goes '''''up'''''. The increase in shield recharge rate continues until it peaks at 25% shield capacity. At this point a buzzer will sound, to warn the pilot that the shield is at its recharging limit. If it continues to take more damage than it can hold, the recharge rate will drop off quickly, and the capacity of the shield will fall towards zero.
 
{{ note box | THE MAIN POINT: In combat the shield will recharge at an increasing rate until 25% of its capacity remains; then the rate will fall off quickly towards zero.}}
 
The shield recharge rate depends on shield maximum capacity and shield recharge time.


Shield recharge rate follows same formula as [[capacitor recharge rate]].
Shield recharge rate follows same formula as [[capacitor recharge rate]].
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The peak recharge Rate is  250% of average shield recharge. It occurs when the capacity of the shield is at 25% of its maximum value. Shield recharge rate drops rapidly below 25% shield capacity.
The peak recharge Rate is  250% of average shield recharge. It occurs when the capacity of the shield is at 25% of its maximum value. Shield recharge rate drops rapidly below 25% shield capacity.


== Technical Section: Fitting Multiple Modules with Stacking Penalties ==
== Fitting Multiple Modules with Stacking Penalties ==
Although it seems laborious, shield fitting requires this computation for each module that incurs a stacking penalty. Note, also, that the use of percentage reductions and stacking penalties is what prevents the total vulnerability from reaching zero. With no vulnerability, the ship would take no damage ... which sounds like fun briefly, but would make for rather boring game play.


This is meant as an illustration. Suppose a ship's base Kinetic damage resistance is 40%. This means that its base Kinetic Vulnerability is 60%. Now suppose that the pilot installs a module that reduces Kinetic Vulnerability by 40%. This makes the reduction in vulnerability 40% of 60%, or 24%. And so the new vulnerability is 60% - 24%, or 36%.
Shield resistance modules are subject to [[Stacking_penalties|Stacking penalties]] which progressively reduce the effectiveness of the modules if they alter the same attribute. In other words, the second module is less than 100% effective, the third even less so, and so on.
 
The penalty only applies to the module's impact on the affected attribute, and progresses as follows:


Now suppose that second module is installed, and that this module has a bonus that reduces Kinetic Vulnerability by 30%. First, because these two modules alter the same attribute, a stacking penalty must be applied. This reduces the "lesser" module's affect to 86.9% of 30%, or 26.1%.
:1st mod: 100.0% effectiveness
:2nd mod: 86.9% effectiveness
:3rd mod: 57.1% effectiveness
:4th mod: 28.3% effectiveness
:... etc.


Since the updated vulnerability from the first module was 36%, the new change in vulnerability is 26.1% of 36%, or 9.4%. This change is subtracted from 36% to get the new updated vulnerability of 26.6%.  
The modules are penalized in order from least effective to more effective - the "best" module for that attribute will be the one that works at 100%; the "second best" one at 86.9%. It is not recommended to fit more than two or three resist modules that are stacking penalized.


This means that with these two modules installed, any kinetic hit will have 73.4% of its damage removed, while 26.6% of the damage will get through. Here is a summary:
In addition to stacking penalties the shield resists aren't added together directly. Two 30% unpenalized resist modules will not give your ship 60% resist profile. You can think that each resist module reduces incoming damage individually. With incoming hit of 100 damage the first 30% resist module would reduce the hit to 70 damage and the second resist module would further reduce 70 damage to 49 damage giving total resist of 51% instead of 60%.


{| class="wikitable" style="margin: 1em auto 1em auto;" style="text-align: center"
! scope="col" width="100px" style="background-color:#222222;" |
! scope="col" width="100px" style="background-color:#222222;"| Base Kinetic Resistance
! scope="col" width="100px" style="background-color:#222222;"| First Module
! scope="col" width="100px" style="background-color:#222222;"| Second Module
|-
|Module Bonus|| - || 40% || 30%
|-
|Penalty|| none || none || 86.9%
|-
|Bonus with Penalty|| none || 40% || 26.1%
|-
|Current Vulnerability|| 60% || 60% || 36%
|-
|Change|| none || 24% || 9.4%
|-
|Updated Vulnerability|| 60% || '''36%''' || '''26.6%'''
|}


[[Category:Ship Fitting]]
[[Category:Ship Fitting]]
[[Category:Tank]]
[[Category:Tank]]
[[Category:Game mechanics]]
[[Category:Game mechanics]]