FOV and Input Lag/Latency

[Bobby Pennington]

I just made a video of what using the correct FOV per all the calculators and the math and how it can destroy your experience. I've been chasing my tail with my G27 settings and it turns out the biggest problem was the stupid FOV.
Visit my boobtube page MulliganF1 for a full description of my setup and explanation.
This is the only way I can give back to the Sim community since I don't make skins, tracks etc., but I'm working on it.
Please let me know if the video helps. Have a great night and as always Opposite Lock to 'ya.

P.S.: I hope I posted this in the correct section. Still learning.

 

[Stefan Sparco]

I used to use the calculated FOV when I had a 40" 4K monitor.
Now I use a 27" 1440P monitor and I use the calculated FOV * 1.5. It's a good compromise for that size screen.

 

[PicoBp]

You don't just see less. The "length perception" is different and is not realistic. My calculated fov would be 15. As i previously stated, the way the track looks like when choosing a lower fov is not realistic. The Fov changes the field of view and is made to have a realistic fov, nothing else. Still, you sacrify realistic proportions.

EDIT: btw, i've already looked at that link months ago. First of all, that's his opinion on whether is important or not to have it, but it doesn't talk about proportions at all, just FIELD OF VIEW.

EDIT2: Of course with the length percetion changes the speed perception as well.

Proportions get wrong with higher than calculated FoV, but only because you tell the game that the monitor fills 50° degrees of your view (from your eyes), when in fact it's only 18° degrees. With these numbers, the proportions become 1/3 of the actual, in other words, you're cramping x3 the information into the same amount of degrees that your monitor fills. Just like when you use a fisheye lens on a camera.

If you need hard evidence, take a screenshot with 50 and then with 18. Go into Photoshop (or the graphics software of your choice), center the two on each other (18 on the top layer) and start reducing it's size with fixed proportions. At around 33-36% size you'll realize that the 18° FoV image matches perfectly with the 50° image, it's just a smaller crop of it.

On a personal note, I also agree that calculated FoV*1.5 is about the good compromise for single screen use, even with the 34" ultrawide I have.

P.S.: Perception is subjective to each, many can seem right based on personal preferences. But proportions are objective, mathematical. There's only one correct number for 1:1 proportion, the one that's calculated with screen size, screen ratio and eye distance. Don't confuse the two.

 

[Bobby Pennington]

I'm using a FOV of 28, which is the calculated one, on my 21:9 ultra-wide singlescreen (BenQ XR3501).
Referring to the opening post of this thread a FOV of 28 should be laggy and undriveable. But for me this is absolutely not the case.

I'd never recommend a drastic change in FOV, because the changes in visual perception are huge. It's not a surprise, that the driving feels different, because distances, road width, turn radius, elevations, etc. differ a lot from a visual point.

FOV is an area, which you have to get used to. If you want to go more into direction of using a calculated FOV, then you should lower the FOV in small steps. Decreasing it 3-5 degrees and drive 2-3 races with it. If you are comfortable with the view, try lowering the FOV a few degrees more. That's how i have done it.

However, if you're using just a small singlescreen, you have to find a compromise, because the calculated FOV doesn't give you enough peripheral vision to drive properly. I think the calculated FOV * 1.5 could be a realistic aim for a small single monitor. And try to have the eye distance to your screen as less as possible.

Frank the lag and being uncontrollable is my reason for the post. My wheel felt too sensitive so I had to use profiler to turn down the steering axis to 20% with fov 28-33. Seems I've confused some with the title of the post. I was just trying to help guys that were having trouble with over driving the car, couldn't figure it out (like me) and this was the result of my experiment.
If I had used the multiplier of 1.5 that BhZ mentioned I probably wouldn't have had as much trouble, but then again I probably wouldn't have ever figured out why my controller had to be turned way down.

 

[Albert McSaltens]

Yes. The visual difference and the difference in speed judgement means you either underdrive or overdrive the car.

The physics do not change, your inputs do because you are seeing a different visualisation of the same thing.

LODS are afected by FOV value higher quality lods less fps

 

[Denis E.]

Hm, now i can't understand what FOV is more correct (real) ?
Early i use projectimmersion to calculate my FOV and have result 48º, but now i find this thread http://www.racedepartment.com/threads/how-to-proper-triple-screens-setup-fov-monitor-angles.123586/ and with the same distance to display, i have result 53º
(vFOV = 2 x {invTan x [(ImageHeight ÷ 2) ÷ ViewingDistance]}
What do you think about this ?

 

[Ian Cameron]

Hm, now i can't understand what FOV is more correct (real) ?
Early i use projectimmersion to calculate my FOV and have result 48º, but now i find this thread http://www.racedepartment.com/threads/how-to-proper-triple-screens-setup-fov-monitor-angles.123586/ and with the same distance to display, i have result 53º
(vFOV = 2 x {invTan x [(ImageHeight ÷ 2) ÷ ViewingDistance]}
What do you think about this ?

I found that thread very confusing, and not brilliant at maths could not understand how to work it out. I used Project Immersion when I had a single screen and seemed to be ok.
Now I have triple screens 3x27" sat 60cm from screen and angled at 60 degrees. If you have triples just use the triple screen app in AC put in your measurements and away you go. I then click auto position and adjust seat to line up with dashboard etc. works well for me, and after along time of playing with FOV settings, finally I'm happy with the set up.