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How to understand "Speed to signature ratio"?
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Deedee Hakata
Hakata Exploration
#1 - 2011-09-10 23:31:33 UTC
So EFT 2.13.4 has added a "Speed to signature ratio" tooltip number to the ship speed. What does this number mean?

For comparison, I can understand it (higher is better), and by fitting an interceptor one can easily get it up to 60 and higher. But what does that mean? Can that number be translated into something useful, like % damage reduction against something? Ugh
Aessaya
Independent treasure hunters
#2 - 2011-09-10 23:37:15 UTC  |  Edited by: Aessaya
I think it can be used to compare different speed-tanking ships and/or setups to assess how well they can perform. I don't see any other non-empirical use to this, since there are usually a lot of other factors that relate to this.

Ah, you seek meaning? Then listen to the music, not the song.
Tippia
Sunshine and Lollipops
#3 - 2011-09-10 23:57:26 UTC
Most directly, it tells you how much you mitigate missile damage.

The missile formula has an [expvel / speed] ÷ [sigrad / exprad] factor in it, and if you switch the variables around a bit, you get a sigrad:speed ratio as one of the quantities involved. The lower this ratio is, the better equipped you are to avoid damage from missiles.

In EFT he has inverted it so you get a more intuitive “higher is better” number.
Aessaya
Independent treasure hunters
#4 - 2011-09-11 00:21:22 UTC
Tippia wrote:
Most directly, it tells you how much you mitigate missile damage.

The missile formula has an [expvel / speed] ÷ [sigrad / exprad] factor in it, and if you switch the variables around a bit, you get a sigrad:speed ratio as one of the quantities involved. The lower this ratio is, the better equipped you are to avoid damage from missiles.

In EFT he has inverted it so you get a more intuitive “higher is better” number.

I'd like to note that speed:sigradius ratio is involved in tracking formula as well, albeit not that directly. That is why i said "speed-tanking" in general.

Ah, you seek meaning? Then listen to the music, not the song.
Tippia
Sunshine and Lollipops
#5 - 2011-09-11 01:24:47 UTC
Aessaya wrote:
I'd like to note that speed:sigradius ratio is involved in tracking formula as well, albeit not that directly. That is why i said "speed-tanking" in general.
True enough, but for tracking, the velocity matters more than just the speed — you can go a million miles an hour, but if it's in the wrong direction, neither the speed nor the sig radius will make even the slightest bit of difference. Not so with missiles.

But yes, as some kind of overall measure of speed-tankyness, it works. It just varies in how true it will be to the actual situation depending on what weapon system you're going up against.
Deedee Hakata
Hakata Exploration
#6 - 2011-09-12 13:41:26 UTC
Is it possible to say anything useful about the ratio itself? (e.g. "If you're in a cruiser-class ship, you should aim for a ratio higher than N"?)
Aamrr
#7 - 2011-09-12 13:42:51 UTC
Outside of comparing the speed tank offered by various interceptors, probably not.
Hamatitio
State War Academy
Caldari State
#8 - 2011-09-13 00:04:24 UTC
Tippia wrote:
True enough, but for tracking, the velocity matters more than just the speed — you can go a million miles an hour, but if it's in the wrong direction, neither the speed nor the sig radius will make even the slightest bit of difference. Not so with missiles.


Angular velocity that is ;P
Aessaya
Independent treasure hunters
#9 - 2011-09-13 03:35:32 UTC
Hamatitio wrote:
Tippia wrote:
True enough, but for tracking, the velocity matters more than just the speed — you can go a million miles an hour, but if it's in the wrong direction, neither the speed nor the sig radius will make even the slightest bit of difference. Not so with missiles.


Angular velocity that is ;P

Well, since you're aiming to be the precise one, it's the transversal velocity. There is a slight difference between those two.

Ah, you seek meaning? Then listen to the music, not the song.
Tippia
Sunshine and Lollipops
#10 - 2011-09-13 06:24:12 UTC
Aessaya wrote:
Well, since you're aiming to be the precise one, it's the transversal velocity. There is a slight difference between those two.
Weeell… angular velocity is the one that ends up being used in the tracking formula, and which is compared against the tracking speed of the turret.
Aamrr
#11 - 2011-09-13 08:57:38 UTC
The trouble with using angular velocity (or even transversal velocity) is that they're particularly variable. Ships move around a lot, and small adjustments in trajectory will cause significant changes in those values.

If you're just trying to see what ships your gang mates are webbing, raw velocity might well be the more useful number for you to look at.
Holy One
Privat Party
#12 - 2011-09-13 11:52:30 UTC
Velocity (as in acceleration), agility, top speed and sig radius are the key things when planning your speed tank. It should be a given that you will be maintaining transversal and angular velocity at all times. Most of the time you will be providing align points, rolling safes, stretching grids or fast primary tackle in an interceptor.

In a non mwd fit combat frigate or a dual prop fit t2 frig, I always go for agility, velocity and top speed.

:)
Vuiko Tarasovich
Bound In Blood
#13 - 2011-09-14 06:50:23 UTC  |  Edited by: Vuiko Tarasovich
Aamrr wrote:
The trouble with using angular velocity (or even transversal velocity) is that they're particularly variable. Ships move around a lot, and small adjustments in trajectory will cause significant changes in those values.

If you're just trying to see what ships your gang mates are webbing, raw velocity might well be the more useful number for you to look at.



Meh, ask your ship mates their velocity or the velocity of their targets and they will give you a wrong answer 90% of the time, velocity is a vector, it requires magnitude AND direction, so you are right in the sense that if you knew your target's velocity you'd have a good chance of knowing if you could hit them (you'd need radius from you to the target as well)

Unfortunately I'm pretty sure your mates don't recognize a difference between speed and velocity, which makes your statement 100% wrong. Speed will tell you almost nothing about whether or not you can hit a ship. A dram moving at 12km/s towards you is 9001x easier to hit than a dram orbiting you while going 12km/s
Aamrr
#14 - 2011-09-14 06:58:20 UTC
Vuiko Tarasovich wrote:
Aamrr wrote:
The trouble with using angular velocity (or even transversal velocity) is that they're particularly variable. Ships move around a lot, and small adjustments in trajectory will cause significant changes in those values.

If you're just trying to see what ships your gang mates are webbing, raw velocity might well be the more useful number for you to look at.



Meh, ask your ship mates their velocity or the velocity of their targets and they will give you a wrong answer 90% of the time, velocity is a vector, it requires magnitude AND direction, so you are right in the sense that if you knew your target's velocity you'd have a good chance of knowing if you could hit them (you'd need radius from you to the target as well)

Unfortunately I'm pretty sure your mates don't recognize a difference between speed and velocity, which makes your statement 100% wrong. Speed will tell you almost nothing about whether or not you can hit a ship. A dram moving at 12km/s towards you is 9001x easier to hit than a dram orbiting you while going 12km/s


I'm not asking my mates anything. I'm watching a column on my overview. And since the velocity column is significantly more consistent (change of direction won't affect it), it's far easier to differentiate what targets are webbed and what ones just happen to be approaching and will be orbiting me shortly anyway.
Vuiko Tarasovich
Bound In Blood
#15 - 2011-09-14 07:19:45 UTC
Aamrr wrote:
Vuiko Tarasovich wrote:
Aamrr wrote:
The trouble with using angular velocity (or even transversal velocity) is that they're particularly variable. Ships move around a lot, and small adjustments in trajectory will cause significant changes in those values.

If you're just trying to see what ships your gang mates are webbing, raw velocity might well be the more useful number for you to look at.



Meh, ask your ship mates their velocity or the velocity of their targets and they will give you a wrong answer 90% of the time, velocity is a vector, it requires magnitude AND direction, so you are right in the sense that if you knew your target's velocity you'd have a good chance of knowing if you could hit them (you'd need radius from you to the target as well)

Unfortunately I'm pretty sure your mates don't recognize a difference between speed and velocity, which makes your statement 100% wrong. Speed will tell you almost nothing about whether or not you can hit a ship. A dram moving at 12km/s towards you is 9001x easier to hit than a dram orbiting you while going 12km/s


I'm not asking my mates anything. I'm watching a column on my overview. And since the velocity column is significantly more consistent (change of direction won't affect it), it's far easier to differentiate what targets are webbed and what ones just happen to be approaching and will be orbiting me shortly anyway.



even if its webbed though, if its angular velocity is too high there's no point in shooting at it.
Aamrr
#16 - 2011-09-14 12:50:10 UTC
If it's webbed, it won't have a high angular velocity. That's why you web it. Roll

The problem is the ships that have a temporarily low angular velocity (such as from approach) which won't stay that way (when they start orbiting). Using raw velocity solves that problem.
Tippia
Sunshine and Lollipops
#17 - 2011-09-14 13:00:46 UTC
Aamrr wrote:
If it's webbed, it won't have a high angular velocity. That's why you web it. Roll

The problem is the ships that have a temporarily low angular velocity (such as from approach) which won't stay that way (when they start orbiting). Using raw velocity solves that problem.
…except that the overview does not offer any “raw velocity” data — only the tactical overview does (and even that is a stretch).

Anyway, the easy solution is to have all three: speed, angular velocity and radial velocity. One to pick the fast ships; one to determine turret effectiveness, and one to determine manoeuvring… although that might just be a holdover from my old flightsim days when closing speed was critical information. P
Aamrr
#18 - 2011-09-14 13:03:30 UTC
*sighs* Raw speed, then. Which is what the overview refers to as "velocity"
Tippia
Sunshine and Lollipops
#19 - 2011-09-14 13:36:14 UTC
Aamrr wrote:
*sighs* Raw speed, then. Which is what the overview refers to as "velocity"
Yes, I know, but I'm being particular because there is an important difference, not just mathematically but (game-)mechanically. Turrets care about velocity; missiles do not (beyond that they're carriers of the speed). Missiles care about speed; turrets do not (beyond how they affect the velocity).
Aamrr
#20 - 2011-09-14 14:24:01 UTC
And now we're arguing semantics. I'm well aware of the difference between the two terms, but I chose to use word used by the overview in-game for the sake of consistency.

The point of my argument remains no matter what you call it though. Angular velocity changes too frequently to discern important details like stasis webification.