FOV Calculator

Discussion in 'General Discussion' started by taufikp, Mar 29, 2012.

  1. Saabjock

    Saabjock Registered

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    View attachment 11496
    Not RF2 (sorry)...but a good representation of my virtual cockpit seating position using a single 24" monitor and seated 3ft away.
     
    Last edited by a moderator: Jan 18, 2014
  2. Pilot37

    Pilot37 Registered

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    I've been trying to get my head around this thread and experimented with the Trigonometry which took my FOV from 76 down to 33 in RF2 and how dull was that!

    I think there is something fundamentally wrong with the depiction on the screen versus real life. I went out and sat in my now unused historic Formula Ford which you pretty well have to lie down in yet can always see both front wheels away in front (just the tyre tops in more recent cars), plus the gauges. The mirrors just give you wobbly glimpses of what your senses already believe is going on behind.

    At lower FOVs everyone is in wonder at their better lap times. Isn't that just because the side affect is that distance appears greatly shortened, slower, calmer, a sort of dull cheat and one that I haven't experienced in a real world racing car. Rattling along missing clipping points happens pretty easily in a noisy, vibrating, cramped and hostile environment where you are too low to see the true shape of corners as you do in a big high road car and the sense of speed is enhanced by being so low to the ground, the rushing of air etc. I don't recall a camera induced FOV shortening effect to help me calmly pick my turn.

    So what is wrong?
     
  3. joekart

    joekart Registered

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    Well explained, I feel the same things .
    The problem is that our eyes have a very wide field of vision .
    It's better with a triple screen, and it would be even better if the VR could give us a field of view of 180 °.
    Maybe someday...
     
  4. ucfquattroguy

    ucfquattroguy Registered

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    A "correct" FOV with single monitor appears "slow" because in real life, it's your peripheral vision that gives you the sense of speed. Only seeing the stuff coming straight at you is going to appear slow because of the lack of lateral movement. Going to a large FOV appears fast, because you're cramming both what's in front of you AND what would be in your peripheral into a small box immediately in front of your eyes.
     
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  5. Christopher Snow

    Christopher Snow Registered

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    What ucfq just said is true, particularly if the monitor is on the small side. If you can picture driving close to a line of fence posts, even at fairly high speeds the posts come at you relatively slowly, and it's only when they flash by in the last few moments as they pass--in the periphery of your vision--that they give you that sense of speed. I haven't yet been able to get my HMD (Pimax 4K) working well enough to try it in any sims, but with an overall FOV of 100 degrees or so (like most of them), some of the "drama" of passing objects is still going to be missing. True too even of projected images like I have used most recently...:



    [this ^ is not me, but my own setup is similar, including having the feet extend out through the lower center of the screen and onto the pedals. It's also what any HMD will have to improve upon for me to prefer using the latter long-term.]

    ...but I'd be surprised if you don't think that is "closer" to what your historic FF car showed you.
     
  6. Lazza

    Lazza Registered

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    Apart from the posts above which I think explain it pretty well, I have to say my own experience is a little different. And I should say up front I have a single not very big screen which isn't very close - I think correct vertical fov is something like 16°. But changing from the 60° or so I'd been using down to 36° not only severely limited my peripheral vision - it made corners feel like corners (wider angle in my vision) and the speeds I was taking them more incredible, plus the widening of braking zones made my braking markers feel deeper into the corner (later) despite the 'stretched' braking zone then being easier to manage as far as picking a braking point.

    Height changes are also more pronounced, and the car bouncing is itself more pronounced, than it was before.

    I know the 'feeling of speed' for what it's worth is reduced, but I'm surprised the other sensations didn't compensate. And it's difficult not to appreciate that when you're looking at an object it's actually appearing the same size to you as it would in real life at that distance. Even when I tried real FOV on my screen and could barely see anything, I thought the distant corners looked pretty cool because they looked the way they really would. Of course most of them I couldn't see when I got close ;)
     
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  7. SPASKIS

    SPASKIS Registered

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    It is clear that using correct FOV in a single monitor makes sensation of speed more difficult to perceive. However as @Lazza says the correctness of aspect ratio is critical in order to perceive turns. Using high FOV straightens turns. I have no problem of perceiving speed using 38. Actually the reason why I don't lower it even lower is because I lose too much peripheral view and I can't see the turn exit. Nothing related to sensation of speed.

    However, this already has a solution. It is called VR and it is already available. It still has a long improvement margin in terms of quality and economic availability but they will come.

    No reason IMO to arise this topic again. If you are not in VR take the FOV that suits your hardware best. If you are not happy still, the problem is your hardware.
     
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  8. SPASKIS

    SPASKIS Registered

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    The FOV being used in the video is way too high compared to mathematically correct one.
     
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  9. Stephen O'Sullivan

    Stephen O'Sullivan Registered

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    Just for fun, here are a few different ways that people have tried to improve immersion. These are best watched fullscreen.

    With a projector (Dirt Rally):



    With triple monitors (rF2):



    Triple monitors with disguised bevels (Automobilista):



    And another over-the-shoulder view but with a single monitor (Raceroom):

     
    Last edited: Jul 15, 2017
  10. Stan

    Stan Registered

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    I allow myself an advice, I think it's a matter of focus... while driving a sim you should not look at the screens, but rather (and as in reality) focusing as much as you can on the farest/furtherest point you can see of the road. It tend to minimise quite well the slowy effect, at least for me!
     
    Last edited: Jul 16, 2017
  11. muz_j

    muz_j Registered

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    I find this Pcars calculator works very well - for me anyway.
    I run my screen around 65 degrees FOV and I personally find that suits me.

    http://carsfov.moritzlawitschka.de
     
  12. Stan

    Stan Registered

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    @muz_j Sorry, but it's totally wrong as pcars use horizontal fov...
     
  13. SPASKIS

    SPASKIS Registered

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    Using 65 vertical FOV for single screen should be considered wrong by itself. Projecting such a big angle on a planar surface provokes image distorsion.
     
  14. Lazza

    Lazza Registered

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    @SPASKIS Unless your single screen occupies 65º of your view vertically, in which case there isn't any distortion at all...
     
  15. SPASKIS

    SPASKIS Registered

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    The distortion I refer is because cosine effect. Above 60 degree in the smaller dimension (vertical in this case) would create a significant distortion from spheric to planar. Using a FOV below 40 reduces distortion to 6% and less. Using FOV 60+ results in a distortion above 14%.
     
  16. Lazza

    Lazza Registered

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    Where's the spheric? The game image is projected onto a virtual planar surface. There's no distortion.
     
  17. SPASKIS

    SPASKIS Registered

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    I imagined it used an angle limited spheric projection which seems easier to perform in terms of maths and where each pixel corresponds to the same sterescopic angle. The typical side stretching that can be perceived when using 3 screens seemed consequence of this distortion to me.

    In any case, although you are probably right I'll try to check that out. ;)
     
  18. Pilot37

    Pilot37 Registered

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    So what is suggested is that even on a 27" screen forget speed sensation and live with a view putting your chin on the bonnet? Perhaps the track surfaces lacking detail and the lighting of doesn't help, most UK tracks are much bumpier and more gritty to race on compared to what is depicted.

    Charging up Avon Rise towards Quarry at Castle Combe always gave you a feeling of "Oh Shit" because you experience side and vertical forces at speed from wind, bumps, gradient changes, bounce and rattle and the sheer amount of crappy looking track rushing underneath you...(and sometimes a slight doubt that you have a clear plan for what happens when you crest the hill)....yet the fences are miles away and there's a cornfield away on your right. Surely we have got some kind of absurd reductio ad absurdum going on here based on maths but missing some other key brain perceptions lost in a camera or a computer screen.

    Without the thrill of speed, noise and a sense that you are just about hanging in there I can't see what the fun is? I'm guessing the majority of us don't have the space or budget for triple screen super rigs? What would have Grand Prix Legends have looked like "FOV'd" in the days when monitors were deeper than they were wide?
     
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  19. Lazza

    Lazza Registered

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    @Pilot37 I don't think anyone's forcing anyone to do anything. Using (more) realistic fov is an option, but it's a personal choice. But as I said above, sense of speed is the only thing you lose. Other sensations are actually heightened.
     
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  20. ceecee

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