Camera position changes car behavior

[GTWelsh]

Is that a bug? The physics model wheels will always react slower than controller inputs because a controller can go from lock to lock in a fraction of a second, a steering wheel, steering rack, wheels and tyres don't, therefore nearly all controller inputs are only dished out from your thumb to the physics engine at a certain rate. This rate is/was also speed sensitive, and that was easy to prove in GT6 using the motec data export. I'd say it was a bug if the graphical representation of the wheels didn't match the physics model of the wheels (in terms of steering angle anyway), but I doubt it's a bug if they don't match thumb inputs.

Yeah I agree, but it appears the physics code that controls the steering runs fine, and the car turns at a normal rate. But graphically the wheels lag behind. This seems to only happen in replays, going very slow and going lock to lock. It's like a wheel smoothing factor is set way to high (the steering wheel has this kinda stuff too, and doesn't represent the inputs (or car outputs) at all. It's way too slow and smoothed).

@Ryan Dungey said he was doing 1:35's with the Huracan with TC at 2. Was that Huracan stock? I can usually get to 1-2 seconds of the top ten, but I can't for the life of me figure out where I am losing 4 seconds at Dragon Trail. What is a normal time? I am flat through most of that track and my fastest is 1:39.2.

A completely stock huracan GT3. Only changes I madebwas brake bias at 2 on the front and TC at 2

My 1.34 was BoP ON, but the suspension and aero was not stock. It's a fast car, just really hard to drive fast consistently.

 

[phil_75]

THIS. Yes. The graphic car and the code/physical car are not the same thing. I was hoping the graphical car would show something but it really appears to just pivot on the center of the rear axle.

I was driving the RSR around Nurb GP seeing if I could beat my bumper time. In the hairpin with the cockpit cam, the RSR is loose. In the hairpin with the bumper cam, it isn't. That got me thinking about the RS01 bug.

Now, this may be related to THIS thread about the RS01 because I tried to recreate this bug and I CANNOT for the life of me make it happen. These guys were going into the hairpin and just cruising around it with no gas or brake and the RS01 was spinning. I was dead set that it was user error. Why was that my opinion? Because in my game, it is IMPOSSIBLE for me to recreate this bug. I couldn't do it back then and last night it dawned on me that maybe it was related.

I have tried all night and all this morning because I was sure this would show what I am seeing, but after what has to be 100+ attempts, I cannot spin the RS01 in that corner the way the guys in the video do it. It simply does not happen for me. Not even close. I want to apologize for being so adamant that their bug wasn't happening because, apparently, We are not playing with the same equal experience.

We are all assuming that everyone has the same things happening, but the grip bug showed us that some people have an extreme advantage. What if my game is different? It's definitely different than the game of the people with the RS01 bug. What if, the reason I feel such an undeniable difference is that mine is, legit, not the same?

@Ryan Dungey said he was doing 1:35's with the Huracan with TC at 2. Was that Huracan stock? I can usually get to 1-2 seconds of the top ten, but I can't for the life of me figure out where I am losing 4 seconds at Dragon Trail. What is a normal time? I am flat through most of that track and my fastest is 1:39.2.

How strange that i also commented in that thread that i couldn't reproduce the issue no matter what.

 

[Voodoovaj]

My 1.34 was BoP ON, but the suspension and aero was not stock. It's a fast car, just really hard to drive fast consistently.

K....this is going down a really bizarre rabbit hole.

My Huracan in first person (let's call bumper cam first person) is nearly undriveable. My Huracan, Stock, in cockpit is a little twitchy, but I can run consistent laps in it. My BoP Huracan is a second slower than my Stock Huracan around Suzuka. Hmm.... 5+ seconds around Dragon Trail. You could have an accident and still finish a second ahead of me in the same car.

Today's Race 3 is Nurb Gr3. I dread this race because I cannot, for the life of me, figure out how to consistently run a fast lap on that track. My best record is 1:57.2 in the 911, but I will run 2:00 most of the time with that car. Is that normal?

In today's GR4 Suzuka race, I tried the 458 because I see ORMA_Snow has it doing a 2:06. In first person view, I run through the hairpin no problem. I look at the apex cone, hit it, accelerate out. In cockpit view, if I do the same thing (at least, if I perceive that I am doing the same thing) I lose the rear as soon as I turn in. I have to run wide of the apex to not spin. Is that normal?

 

[GTWelsh]

K....this is going down a really bizarre rabbit hole.

My Huracan in first person (let's call bumper cam first person) is nearly undriveable. My Huracan, Stock, in cockpit is a little twitchy, but I can run consistent laps in it. My BoP Huracan is a second slower than my Stock Huracan around Suzuka. Hmm.... 5+ seconds around Dragon Trail. You could have an accident and still finish a second ahead of me in the same car.

Today's Race 3 is Nurb Gr3. I dread this race because I cannot, for the life of me, figure out how to consistently run a fast lap on that track. My best record is 1:57.2 in the 911, but I will run 2:00 most of the time with that car. Is that normal?

In today's GR4 Suzuka race, I tried the 458 because I see ORMA_Snow has it doing a 2:06. In first person view, I run through the hairpin no problem. I look at the apex cone, hit it, accelerate out. In cockpit view, if I do the same thing (at least, if I perceive that I am doing the same thing) I lose the rear as soon as I turn in. I have to run wide of the apex to not spin. Is that normal?

There is a video of my 1.34 in this thread. Get some tips from that . I used that car almost since release, I put over a hundred hours into it and hundreds of laps around Dragon Trail and only ever got that one 1.34 1.35.5 was easy-ish to do though. This was pre BoP nerf. I have recently done a 1.34 in the GTR though, after the BoP update . I've since become tired of the Lambos crazy handling and I'm using the GTR all the time now .

I've raced DR:S racers 1 on 1 and I can be pretty sure my grip levels are completely normal, as I got my arse handed to me.

 

[Vader86]

I've always been a bumper cam driver, but when I was driving some Gr3 qualifying laps and was messing with settings, I kept seeing the car rotate better when i was in the cockpit compared to anywhere else. Bumper wanted to understeer more. Lap times were about the same but it felt like an easier lap.

 

[thestig911]

Didn't Kaz say he thought the roof view was easier, this the reason they decided not to give it a rear view camera?

My roof view has a rear view!
Just trying it out using Gr4 WRX at interlagos. Immediately a tenth or two quicker, seem to be more consistent.

 

[thestig911]

I was until now, a die hard chase cam user. I raced chase cam in a WRX at interlagos Gr4 race yesterday, my quali time was about 1:40.5. My quali laps were all over the place. I am Dr B at the moment but only just. I fluctuate between C and B

I have just done 9 laps at Interlagos in the same car with roof cam.
Straight away I was at 1:40.4.
My next 4 laps were all low 40s within .4 of a sec, so very consistent.
I then did a couple of mediocre laps.
I then hit 39.9 and then 39.7 with a theoretical optimal of 39.4.

My conclusion is it helps you find a better line more on the edge, and to do so more consistently, you are able to push it more, and therefore able to find more marginal improvements.

 

[D3V]

Sounds very interesting. But how could we test, if thats really the case.
My thoughts about this (how testing could get accurate)

Spoiler: Offtopic Thoughts about Testing

Since it's easily possible to use your DS4 on Mac/PC/Ipad/... and so on, it would be good for testing if you could "record" your Lap(inputs), and then replay it. So it would be everytime exact the same inputs on your PS4 (delay).

I searched around the Internet if something exists. Badly (and somehow luckily), i could'nt find anything near what i want. Emulate a DS4 Controller with your PC (that the Computer is your DS4-Controller).

It's possible to use your DS4 with a micro-usb cable on the PS4, so i thought about a "Man in the Middle"-Idea with the Controller. Hook up your DS4 with a Cable to your Computer, then connect (with a Usb-Usb Cable) your PC to your PS4. (The PC would let the Inputs throuh to your PS4, and you could record it, then Replay)
(Ok it would be then a "PC in the Middle"-Thing :-P )

But so, it would be possible to test such stuff properly (since testing Games/Software died a long time ago)

And yeah i know, such stuff should'nt be released to Public, cause then you'll never know if you play against "Bots". But i'm just a bit dissapointed of Software/Games, which is full of Bugs at release.
(there was a time, stuff was tested properly before released, i didn't cared if the release was delayed for months)
That was the "Out of Box Time"

Perhabs i'll dig into that once...
I'll write some Github-Guys about that, i'll hope for good answers.
EDIT: After searching a bit more, i've found something similiar. It's called "PS4 Remote Play Interceptor" --> Youtube-Video

Good or Stupid Idea ¿

@Voodoovaj
Sorry for missusing your Thread

 

[Voodoovaj]

My roof view has a rear view!
Just trying it out using Gr4 WRX at interlagos. Immediately a tenth or two quicker, seem to be more consistent.

What? How? My roof view doesn't have a rear view.

Btw, I may have stumbled om something.

I changed the force feedback settings. Although I am on a controller, mine was set to 6/6. When I set them to 1, I went 2 seconds faster than my previous bumper cam lap and a little over a second faster than my in-car. (dragon trail/huracan gr3)

I tried the settings at 10/10 and had the same results.

I put them back to 6/6 and the car seems loose again. I could not keep up, but I wasn't really struggling like I had been.

Seems coincidental to me right now, and it's hard to tell. But, maybe, the FFB is triggering and reducing/changing steering input. Having different cams is changing my line aand therefore changing the FFB. In fact, simply changing it may have eliminated the bug. All I know is that Huracan is driving differently, and consistently, after that change.

 

[Nando deBem]

Guys... we’re not consistent enough to make tests based on lap times. I’d say aliens are not too... but they’re more than us... if you wanna test something, again, control the variables. Guys doing 1:45 at Dragon Trail saying there’s something wrong because they were able to lower their time... yep, there was... your driving!
That’s too far away from the limit to think it’s the camera. Hundreds of different things you might be doing different for every lap.

 

[Voodoovaj]

Guys... we’re not consistent enough to make tests based on lap times. I’d say aliens are not too... but they’re more than us... if you wanna test something, again, control the variables. Guys doing 1:45 at Dragon Trail saying there’s something wrong because they were able to lower their time... yep, there was... your driving!
That’s too far away from the limit to think it’s the camera. Hundreds of different things you might be doing different for every lap.

Agreed. I was hoping to see consistency in behaviour, but that's not happening.

Like the RS01 bug, we can't find consistency where we should. All I know is something is not right on my end and apparently it's not a game wide issue as I assumed it was.

 

[vvise]

Guys... we’re not consistent enough to make tests based on lap times. I’d say aliens are not too... but they’re more than us... if you wanna test something, again, control the variables. Guys doing 1:45 at Dragon Trail saying there’s something wrong because they were able to lower their time... yep, there was... your driving!
That’s too far away from the limit to think it’s the camera. Hundreds of different things you might be doing different for every lap.

this is exactly how i feel in all the respective "bug" threads. glad i'm not the only one taking crazy pills.

 

[Draggon]

Different cameras give different perspectives how the car is behaving and is placed on track. Bumper cam gives you precision, but it's harder to judge oversteer.

A bit of 1:1 stuff to throw in. When drag racer Don Garlits debuted a rear engine AA/FD in 1971 it handled horribly and he found it almost impossible to drive. Eventually he slowed down the steering ratio way past what would be considered acceptable. Driving from much closer to the front axle changed the perceptions immensely and it was near impossible to tell what the back end of the car was doing until it already had. Slowing the ratio down effectively slowed the time between steering input and reaction at the front wheels.

If the physics in the game are not different with camera postilions this would make sense.

 

[Voodoovaj]

A bit of 1:1 stuff to throw in. When drag racer Don Garlits debuted a rear engine AA/FC in 1971 it handled horribly and he found it almost impossible to drive. Eventually he slowed down the steering ratio way past what would be considered acceptable. Driving from much closer to the front axle changed the perceptions immensely and it was near impossible to tell what the back end of the car was doing until it already had. Slowing the ratio down effectively slowed the time between steering input and reaction at the front wheels.

If the physics in the game are not different with camera postilions this would make sense.

I have never suggested the physics was changing, just the behavior.

It still seems like WAY more than a perception. I was playing with the brake bias and in first person view, I can drive a lap no problem with 4 to the rear. I switch to cockpit view and go spinning off the track the moment I hit the brakes.

It absolutely could just be the change of position, but it sure feels like a lot more.

I broke out the Z4 today for the Nurb race because I was tired of getting my butt handed to me lap after lap. It was one car that I could normally run 1:58-1:59 with during the race. Today I was running 2:00 - 2:02! I exited the race and tried to use it to qualify, which I normally do. My best lap with it, before today, was 1:57.8. Today, I can't get below 2:00.

Something is not right. This isn't just in my head. Something is not right with my game. Nothing is predictable. I don't know what is happening anymore, but this isn't a good time.

 

[DriftMethod]

I have never suggested the physics was changing, just the behavior.

It still seems like WAY more than a perception. I was playing with the brake bias and in first person view, I can drive a lap no problem with 4 to the rear. I switch to cockpit view and go spinning off the track the moment I hit the brakes.

It absolutely could just be the change of position, but it sure feels like a lot more.

I broke out the Z4 today for the Nurb race because I was tired of getting my butt handed to me lap after lap. It was one car that I could normally run 1:58-1:59 with during the race. Today I was running 2:00 - 2:02! I exited the race and tried to use it to qualify, which I normally do. My best lap with it, before today, was 1:57.8. Today, I can't get below 2:00.

Something is not right. This isn't just in my head. Something is not right with my game. Nothing is predictable. I don't know what is happening anymore, but this isn't a good time.

Maybe you got the Slip Bug

 

[Voodoovaj]

Maybe you got the Slip Bug

Ya, no kidding.

So here's how my day went. After all this back and forth and feeling down, I decided "maybe I will clear my cache". That's always a good place to start when things get weird.

I grabbed an SLS and went to the livery editor. The tires didn't match the wheel size. I changed the wheels and that reset everything.

I went back to Nurb where I couldn't do a damn thing with the Z4 earlier. I was +1.7 second slower than my best on the opening of the lap. The car was all over. Red sectors everywhere. Then, it simply got better. The pace game back. All blue sectors and I was on pace to beat my all out lap record. I screwed up a little and did a 1:58.0 (which is normal) and I will likely go back and try again later.

I noticed that I had a save game upload error from two days ago, around the same time as I started to see all this weirdness.

I don't know what I just went through, but for the love of all that is holy, I never want to go through that again!! Hopefully, it was just bad data somewhere that has now been cleaned up.

 

[ScottPuss20]

Camera position doesn't change car behaviour, it changes your behaviour. Certain camera views can alter your driving style, for better of for worse, being influenced by how you see the road, take the lines, and see other cars. Example being: I am much slower in cockpit view compared to chase cam because there is less visibility; which makes me less daring compared to chase cam. Give it enough time however and I would be able to get similar times, but because I've become accustomed to chase cam, it's the view I'm fastest with.

 

[Sander 001]

Agree 100%

I think people will experience it more with cars with no aero and sport tyres.

Was trying some setups with friends on RX7 with sport mediums, all aids off, (I use chase cam), back end was sliding all over the place, changed to cockpit view and felt like a different car, went 4 secs+ a lap faster.

Difference was like driving on ice to having superglue for tyres.

It was a 6 lap race @ Nurb Gp, weather fine - did 3 laps going sideways with normal chase cam then 3 laps in cockpit view chucking the car around...

It was the same on previous GTs, cars were always more stable in cockpit view compared to chase cam. Chase cam has that horrible twitch (turning in after braking) that means you have to wait a tiny bit extra for car to settle. Worst case scenario is the sideways rotation, the car starts to slide after outside rear wheel gives up and it's gone.

I'm a chase cam user and had no idea the transition from braking to throttle in the corner could be done smoothly and without delay! Well now I tried it and did 2 full Sport Mode races(came in 2nd and then 1st) and you can absolutely get on the throttle right away and with less fear of spinning. Also, if you do go too hard, it's much easier to catch that spin.

Another thing which has convinced me that there is a physics change is that halfway through a qualifying session, I switched back to chase cam and it did not feel like it usually does. But after I quit the session and restarted with chaser cam, it felt like normal.

I wonder if this is related to the grip bug thread in that it's possible to get the benefits of all the different cams at the same time.

 

[Highlandor]

I'm a chase cam user and had no idea the transition from braking to throttle in the corner could be done smoothly and without delay! Well now I tried it and did 2 full Sport Mode races(came in 2nd and then 1st) and you can absolutely get on the throttle right away and with less fear of spinning. Also, if you do go too hard, it's much easier to catch that spin.

Another thing which has convinced me that there is a physics change is that halfway through a qualifying session, I switched back to chase cam and it did not feel like it usually does. But after I quit the session and restarted with chaser cam, it felt like normal.

I wonder if this is related to the grip bug thread in that it's possible to get the benefits of all the different cams at the same time.

Cool, thanks for that 👍

I think the problems are more than what most people realize, I think the 'grip bug' is a genuine issue but issue's with the physics go alot deeper.

The way I see it is that the physics (the calculation / equation / algorythm in the game), this gets a load of variables ie car, tyres, track, weather, driving aids etc etc etc which goes into the equation and out the other end pops 'X' amount of grip / stability.

But somewhere / somehow, even when the same variables go in, the 'X' that pops out, can differ.

I was testing out the tracks and weather conditions with the same car, GT86, stock with sports mediums, all driving aids off, tyre wear @ x5. I tried various tracks with the 3 different types of weather conditions (cloudy, fine & sunny). At first it seemed like there was a pattern, but that was just one run in one lobby with the 3 different weather conditions @ 3 different tracks (Brands, Suzuka & Nurb gp). After using this as a 'base test' over the past 6-8 weeks for a roadcar series I've been running, I now couldn't tell you what options to set to get the better grip.

At first setting track to cloudy seemed to give much better grip, until the RX7 and other FR cars felt like they were driving on ice @ Nurb gp. Changed to sunny and all of a sudden they were glued to the track (much the same as changing from chase cam to cockpit during a race there). Happened at both Nurb gp and the Lake Maggiore (whatever it's called) track.

The only conclusion that I come to was that PD has put something into the equation that randomises the grip / stability 'X' that pops out in an attempt to replicate real life differences i.e. when you hear commentators talking about a track becoming 'green' etc in real life. PD has chucked this random factor into the equation to try and mix things up a bit, but it's alot more random than what they anticipated / meant it to be.

It's not something you pick up on as much when you have an abundance of grip and stability i.e. racing tyres and aero. I started doing the daily races a little while ago with the GR3 & 4 cars and have been quite surprised at how much more consistent the cars felt from track to track etc. For me, it seems to be more noticable when it's just the natural mechanical grip of the car being used ie no aero, lower compound tyres.

It's difficult with so many variables having some kind of impact, with so many different ways for people to experience the game too, getting any kind of definitive overall guide or breakdown of what's what is going to be extremely difficult.

 

[VFOURMAX1]

The only conclusion that I come to was that PD has put something into the equation that randomises the grip / stability 'X' that pops out in an attempt to replicate real life differences i.e. when you hear commentators talking about a track becoming 'green' etc in real life. PD has chucked this random factor into the equation to try and mix things up a bit, but it's alot more random than what they anticipated / meant it to be.

I do think the different "times" of the day on track are supposed to mimic grip as associated with the track temps, dew on the track in early morning or at sunrise whatever with the best grip being on a midday sunny time frame for a ""warm" track surface and grip decreasing in an evening setting as the track cools.

I have also experienced the major differences in time I am able to duplicate in Time trials using the same variables and car and also have personally experienced the 2 or so seconds difference in lap times from one visit to the next at times.

I have always just chalked it up to just myself not being able to run the laps as good on a given day but do not actually believe I am off by that much that often. This is not something that has happened only once or twice since game launch.

Even trying to practice offline and setting the same perimeters exactly the same the grip levels between online and offline will not feel or react the same. Grip with acceleration, cornering and braking most always seems to be better in the offline mode over the online mode.

Even when racing against the AI which should account for the difference in a clean air versus dirty air or slipstream effect the grip is still better offline so the air or slipstream argument does not seem to be the root cause either.

I am not the fastest driver by a long shot but I am consistent and I can usually run multiple laps within a few tenths of each other. This is the same even when I cannot duplicate my better times the laps I am able to turn time wise are still within a few tenths over multiple laps. That in itself makes me question whether it is me missing the marks to point that justifies that much inconsistency.

I also quit trying to bring up the game from a "rest" power state as my G29 will not have the same force feedback when brought up from rest mode as it will from being powered back on or restarted totally with GTS. This does not happen with any other game.

 

[thestig911]

What? How? My roof view doesn't have a rear view.

Btw, I may have stumbled om something.

I changed the force feedback settings. Although I am on a controller, mine was set to 6/6. When I set them to 1, I went 2 seconds faster than my previous bumper cam lap and a little over a second faster than my in-car. (dragon trail/huracan gr3)

I tried the settings at 10/10 and had the same results.

I put them back to 6/6 and the car seems loose again. I could not keep up, but I wasn't really struggling like I had been.

Seems coincidental to me right now, and it's hard to tell. But, maybe, the FFB is triggering and reducing/changing steering input. Having different cams is changing my line aand therefore changing the FFB. In fact, simply changing it may have eliminated the bug. All I know is that Huracan is driving differently, and consistently, after that change.

I don’t know how, but my roof view has a rear view. Have now used roof view in 2 cars GR3 WRX and GR4 GTR and they both have rear views.

 

[miata13B]

I don’t know how, but my roof view has a rear view. Have now used roof view in 2 cars GR3 WRX and GR4 GTR and they both have rear views.

Are you using a button to look back or do you have a rear view mirror in that view setting?

I have a button to look behind me that I use an am able to use it with the hood view myself.

 

[Voodoovaj]

Camera position doesn't change car behaviour, it changes your behaviour. Certain camera views can alter your driving style, for better of for worse, being influenced by how you see the road, take the lines, and see other cars. Example being: I am much slower in cockpit view compared to chase cam because there is less visibility; which makes me less daring compared to chase cam. Give it enough time however and I would be able to get similar times, but because I've become accustomed to chase cam, it's the view I'm fastest with.

Well, it WAS changing the behavior of my cars, but as things became progressively worse and unpredictable, it went from a revelation about how the game works to a realization that my game was massively screwed up. The final straw was when the same brake bias caused me to spin out in cockpit view regardless of where I applied the brakes.

in Race 3 yesterday afternoon, my pace was in the 2:02's and I was hanging on for last and frustrated to no end.

Flushed the cache, restarted the game, and restarted the PS4 for good measure.

Last night, my race pace was 1:59's-2:00's and I was fighting for a podium. I am glad that this was not a permanent change, but now I am paranoid about every little thing that goes wrong.

 

[phil_75]

The people saying it can't possibly be a different rotation point with different camera views because "they don't have different physics" or whatever,
Adjusting brake balance changes where the car rotates from doesn't it or is that a placebo too?

 

[GTWelsh]

The people saying it can't possibly be a different rotation point with different camera views because "they don't have different physics" or whatever,
Adjusting brake balance changes where the car rotates from doesn't it or is that a placebo too?

With the brakes ON, changes in bias will change where the car rotates from yes.
I'm not sure about this next point but if people are using driving aids, they may incorporate the brakes, and bias changes could alter the behaviour off the brakes. Potentially anyway.

Edit: Second point is probably wrong the more I think about it, clever TC systems will individually brake a specific wheel, rather than use the bias setting.

 

[Hallitrd]

I did some Dragon Trail Gr.3 lobby races today with the BMW M6 monster, trying out new camera view. As a die hard chase cam user, I'm now practicing with the roof cam. Strange to say, I noticed that it seems easier to control the car (no aids, except abs) with the roof cam, and preventing it going into wheel spin in tight bends.
I switched the camera for each lap (10 laps in total) between chase cam and roof cam, and there was no doubt, it was a bit harder to keep it under control, and not let it go into wheel spin with chase cam.
I don't really know if this is just an illusion and just something in my head . I use DS4 pad, but I can't wait to test this again with wheel and pedals, and see what happen.

 

[Sander 001]

I was watching somebody's race on Brands Hatch yesterday and was immediately struck by how much grip they had. I use roof cam and this person was using bumper cam so I tried it and there does seem to be more grip!

I did some time trials, set a good time from my roof cam and when I switched to bumper, I was able to beat it in 2 laps even though I've never used it before!

 

[Voodoovaj]

I just don't know for sure. When I had this issue, there was no doubt the car was behaving differently. Once I cleared the cache and restarted everything, it seemed that the differences were minor and more attributable to the camera location, where as before all the cache clearing and such, the cars drove completely different.

Might be a strange bug or it might just be perceptual. I can't say for sure anymore.

 

[DriftMethod]

I was watching somebody's race on Brands Hatch yesterday and was immediately struck by how much grip they had. I use roof cam and this person was using bumper cam so I tried it and there does seem to be more grip!

I did some time trials, set a good time from my roof cam and when I switched to bumper, I was able to beat it in 2 laps even though I've never used it before!

I'm fairly certain the point of view changes your driving. I use bumper cam and very occasionally use roof cam to see if I'm losing time in certain corners. For me, there is something about switching between these views that helps to fine tune my driving.

For further argument. Look at youtube videos of the fastest drivers. A lot use the roof cam and I doubt they would be giving up any advantage.

 

[BSDShoes]

FOV affects how your lap times are as well, it happened to me with Project CARS, at one time I had the wrong FOV and once I corrected it I was gaining huge time in laps.

I noticed chase in GTS is fairly low FOV (55?) compared to bumper, and cockpit seems the most accurate FOV. I'd be using cockpit more often if it had the tools that bumper cam has during races.