FOV Calculators cant be right

There is something that has been bothering me for a while, ive read up on FOV in lots of articles and watched some youtube videos too. The premise is that an FOV calculation is suppose to set it up so that what you see on your monitor reflects a true 1:1 with the real world. I have a single 27" monitor and sitting (eye to center of monitor) 24 inches from the monitor which gives me a vFOV of 31 degrees. The monitor sits right behind my wheel so I have setup the virtual seating position to reflect this, so the cars dials look like they would look if they were right behind my logitech wheel. But the problem is this. The dashboard looks great but the virtual world is way too small to be 1:1. For example I've risked looking like a fool in traffic and held out my hands behind my steering wheel about the width of a 27 inch monitor and in traffic. When parked behind another car in the real world it totally fills that width of my hands, accounting for my cars bonnet/hood and that the car is a meter away from the bonnet. When parked behind a virtual car in my sim it does not fill the width of the monitor at the suggested 31 degrees. Neither does the pit "lollipop" man in assetto corsa on the nordschleife pits. Only if i drop my fov some 5-10 degrees do objects start to fill my monitor the way they would in real life. What is causing this, am I doing something wrong? Thanks for any advice
 
Well, it's interesting topic, but maybe you should not obsess about it too much. Your brain can adapt to even major inaccuracies.

Otherwise, there's too much at play here: 27 inch monitor at 24 inches distance, but do you measure it at proper seating position? When in car, do you sit at the same position at the same distance? 24 inches is about arm's length... "about the width of a 27 inch monitor" might be significantly off as well.

Then there's the types of focus, which might or might not be connected to fov and might or might not be connected to 3d to 2d conversion, like the fisheye and close-up lenses in a camera... also, you might be wearing glasses in one of the occasions, which can change things as well.

Also, did you try the same in another sim?
 
Sup @s2173 I will try measure my proper seating position in my car and see if i can replicate that with the SIM. I have one other sim racing game which is automobilista (which btw has the best FFB I have ever felt, wish this FFB was in assetto) and it also uses vFOV and also suffers the same issue I am having. I wouldn't say im obsessing over it as I do enter races online at the suggested FOV, its just given what I have read on what FOV is, its bothered me that things didn't end up looking truly life size so I wondered if it was something i was doing wrong or if its a norm.
 
This is how it looks to me. Which compares pretty well to how it looks in RL.
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I think I run a slightly smaller fov, since I have a 24" monitor.


One thing you can do regardless of FOV, to make sure you're comparing apples to apples, is measure one thing against another within the image. For example, if your driving position is the same, the steering wheel will be a bit less than twice as wide as a car in front of you at any FOV.
 
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Calculated FOV will always be impossible to drive on unless you have a very large screen.

As for the "what fills the screen in AC vs what fills my 27" hands irl" I would say you are indeed doing something wrong. The FOV calculator you use is either a vertical or horizontal angle one. Make sure you use one that matches what AC is.

But anyway you will not drive on that calculated FOV since you won't even see the apex coming up on most corners unless you sit incredibly close to the screen.
 
First world problems. My display is also hanging in front of my wheel. Its 96 Inches (8 feet) across the diagonal and the wheel isn't to scale...

I can live with it.

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My pic was staged, I sit a few meters back from the projector screen. In the same location I watch movies from.

Ive tried closer (not as close as in the pic) but you end up having to rotate your head to look around the screen.

Big is good though, The immersion is pretty damn incredible.
 
Sup @s2173 I will try measure my proper seating position in my car and see if i can replicate that with the SIM. I have one other sim racing game which is automobilista (which btw has the best FFB I have ever felt, wish this FFB was in assetto) and it also uses vFOV and also suffers the same issue I am having. I wouldn't say im obsessing over it as I do enter races online at the suggested FOV, its just given what I have read on what FOV is, its bothered me that things didn't end up looking truly life size so I wondered if it was something i was doing wrong or if its a norm.

Well, nothing's going to look "life size" on a 27" monitor. I used to run three 32" monitors and I loved how big everything looked and felt closer to life size (a car pulling up in the side monitor was actually a bit unnerving because it was so big) but they still weren't actually life size. The monitors were actually poor quality tv's though and I recently upgraded to three 27" monitors and while the quality, crispness, and smoothness is a mahoosive improvement the down-scaling of size has been a bit of a disappointment because the track width looks smaller, trees look smaller, other cars are less intimidating, and all that had a bit of a hit on the immersion level. But the picture quality improvement was still totally worth it.

As for the FOV, I start with the calculated FOV and then do some slight tweaks to suit my taste, so if you have to go up a couple degrees to make it more liveable that's fine.
 
I don't know how a chipmunk would feel driving a car, so I'll leave that to your expertise.

In practice it feels about life sized and gives far better impression of cambers and elevations.

In my experience, Having the game fill my field of view is a more enjoyable and more immersive experience then trying to have the full game world displayed through a small screen.

I am more competitive though on my other setup which runs through a 32" monitor, I put it down to projector lag
 
With FOV you're really just getting closer to reality. There are too many variables to make everything match up to reality without going into some pretty elaborate set ups. I widened the FOV slightly from what the calculator says because it's just to narrow a view. VR and 3 screen is about the only way to make it feel like you're not losing out.
 
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