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Little help after using lut generator...

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456
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513
Been using AC since I got it with no post processing force feedback. Tonight I decided to try it with a custom lut enabled from lut generator. Big time improvement in feeling the subtle road bumps and such, but there are two things missing.
The wheel has no weighty feel to it anymore. It feels like i'm turning on ice because I can't feel the tyres through the wheel and there's no resistance or strength to rotating it. Secondly, I don't feel the wheel slip like I did before when I step on the gas too strong mid turn or coming out of a turn so I can't tell when i'm losing the car.

What two options can I look to to try and get some of those two effects back. I'm assuming I can raise the slip effect percentage to get more wheel spin effect, but i'm not sure what to do about the loss of strength in rotating the wheel?

Thanks for any advice...
 
Messages
317
Points
451
All the LUT will have done is emphasised or de-emphasised str0ng and weak forces. Given the flaw in the wheelcheck and the usual process people use for generating a LUT typically what happens is all the weak forces get increased and the strong forces get reduced. So just editting that last part of the LUT above 30% or so to be linear to the top will probably fix the primary forces.

I should note that LUT generation is based on a flawed premise that the wheels aren't linear, this is not actually the case. Wheelcheck checks the speed and distance the wheel travels, but due to resistance in the gearing and maximum speed of the motor (neither of which impacts your force feedback as you feel it) this causes the end result to be heavily biased and limits the travel at higher speeds and at very low forces. Someone tested their wheel in wheelcheck and with a broom touching a scale and came to the conclusion their wheel was in fact completely linear and wheel check gets it wrong, it uses a proxy measure that has turned out to be useless. This has been known for years now. So if you want to adjust it be aware it is because you want it that way, not because there is an issue with the wheel linearity. Thus you should manually edit the LUT as part of overall FFB tuning, other avenues are usually better to achieve what you are looking for in FFB adjustment in my experience.
 
Messages
456
Points
513
All the LUT will have done is emphasised or de-emphasised str0ng and weak forces. Given the flaw in the wheelcheck and the usual process people use for generating a LUT typically what happens is all the weak forces get increased and the strong forces get reduced. So just editting that last part of the LUT above 30% or so to be linear to the top will probably fix the primary forces.

I should note that LUT generation is based on a flawed premise that the wheels aren't linear, this is not actually the case. Wheelcheck checks the speed and distance the wheel travels, but due to resistance in the gearing and maximum speed of the motor (neither of which impacts your force feedback as you feel it) this causes the end result to be heavily biased and limits the travel at higher speeds and at very low forces. Someone tested their wheel in wheelcheck and with a broom touching a scale and came to the conclusion their wheel was in fact completely linear and wheel check gets it wrong, it uses a proxy measure that has turned out to be useless. This has been known for years now. So if you want to adjust it be aware it is because you want it that way, not because there is an issue with the wheel linearity. Thus you should manually edit the LUT as part of overall FFB tuning, other avenues are usually better to achieve what you are looking for in FFB adjustment in my experience.

What you said in the second paragraph went right over my head and now 'i'm not sure what i'm supposed to do. Are you saying not to use ffb post processing because it's flawed and I should just stick to what i've been doing by not using any ffb post processing? Or is it ok to use Gamma post processing but not lut post processing because only lut is flawed?
 
Last edited:

RasmusP

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All the LUT will have done is emphasised or de-emphasised str0ng and weak forces. Given the flaw in the wheelcheck and the usual process people use for generating a LUT typically what happens is all the weak forces get increased and the strong forces get reduced. So just editting that last part of the LUT above 30% or so to be linear to the top will probably fix the primary forces.

I should note that LUT generation is based on a flawed premise that the wheels aren't linear, this is not actually the case. Wheelcheck checks the speed and distance the wheel travels, but due to resistance in the gearing and maximum speed of the motor (neither of which impacts your force feedback as you feel it) this causes the end result to be heavily biased and limits the travel at higher speeds and at very low forces. Someone tested their wheel in wheelcheck and with a broom touching a scale and came to the conclusion their wheel was in fact completely linear and wheel check gets it wrong, it uses a proxy measure that has turned out to be useless. This has been known for years now. So if you want to adjust it be aware it is because you want it that way, not because there is an issue with the wheel linearity. Thus you should manually edit the LUT as part of overall FFB tuning, other avenues are usually better to achieve what you are looking for in FFB adjustment in my experience.
THANK YOU!

Has to be said! The creator of the LUT generator doesn't even have a Logitech wheel! I've read that somewhere in the masses of posts about it (post by him, that he has not driving a Logitech wheel!).
 

RasmusP

Premium
Messages
7,491
Points
7,022
Been using AC since I got it with no post processing force feedback. Tonight I decided to try it with a custom lut enabled from lut generator. Big time improvement in feeling the subtle road bumps and such, but there are two things missing.
The wheel has no weighty feel to it anymore. It feels like i'm turning on ice because I can't feel the tyres through the wheel and there's no resistance or strength to rotating it. Secondly, I don't feel the wheel slip like I did before when I step on the gas too strong mid turn or coming out of a turn so I can't tell when i'm losing the car.

What two options can I look to to try and get some of those two effects back. I'm assuming I can raise the slip effect percentage to get more wheel spin effect, but i'm not sure what to do about the loss of strength in rotating the wheel?

Thanks for any advice...

What you said in the second paragraph went right over my head and now 'i'm not sure what i'm supposed to do. Are you saying not to use ffb post processing because it's flawed and I should just stick to what i've been doing by not using any ffb post processing? Or is it ok to use Gamma post processing but not lut post processing because only lut is flawed?

Which wheel are you using?

If you have a Logitech wheel: use my LUTs
If you don't have a Logitech wheel: don't use any LUT

Simple as this...
Gamma is okay to use, if you like it. It's not some weirdly shaped table that will have steps in the ffb strength.

Gamma works as a smooth curve that will either boost lower forces so the wheel feels heavier in general but you're sacrificing details in the higher forces.
This would be for gamma values between 0.1-1.0.

Or it make the wheel softer in general but will boost the difference at higher forces.
Gamme values above 1.0

About my LUTs:
Logitech wheels have a BIG deadzone and the minimum force setting in AC isn't very smooth. You start to feel a notch in the center although there's still a deadzone. Impossible to find the "best" value.

My LUTs only do one thing:
Smooth the minimum force setting.
With my LUT's the ffb will drop off in a curve, instead of just raising the beginning of the ffb.

The idea comes from Project Cars 1, where you have "deadzone removal" and "deadzone removal fall off".
Which is basically "min force" and "min force drop towards 0%".
 

Stereo

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I would recommend against gamma in favour of the CSP ffb tweaks 'range compression', same functionality but it eliminates a problem with the derivative being infinite at the center when you use it to increase lower forces. Also it's simpler to explain - you set it to the relative strength you want for small forces. (100% = linear). So if you want stronger small forces you bump it up. Mostly useful for lower end wheels on aero cars, where they'll end up not generating enough force at low speeds to even feel it, this can amplify those small forces.

If you want to be fancy you can also use it to increase headroom before clipping; setting overall strength to half as much and range compression to twice as much will leave small forces the same but squish large forces into a narrower range, so it doesn't clip until the force is twice as high. In principle this is similar to what power steering assists do (low forces are unassisted, high forces reduced).

You can do this with a LUT as well but it'd be harder to adjust that smoothly.
 
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