Proper 21-9 Support

[Donut]

I could very well be the dumb one here, but I just don't get it.  It's not what I am seeing and not what examples from other sims/games show.

 

I need pictures/examples..lots and lots, and maybe beer...oh, and donuts. 
 

Thank you to all who are taking the effort to get this understood.

[Tippis]

29 minutes ago, Donut said:

This where I am not understanding things.  A 21:9 has more pixels than  16:9 as well as should display more cockpit real estate horizontally...all while being at the same FOV/zoom level.  

No, because that's not what FoV is.

If you have more horizontal pixels but the same FoV, what happens is that you see the same horizontal cockpit real-estate — because that's the horizontal real-estate the FoV covers — but you'll see it at a higher resolution.

 

3440 pixels shown at a 75° FoV ≈ 46 pixels per degree.

2560 pixels shown at a 75° FoV ≈ 34 pixels per degree.

More horizontal pixels + same horizontal FoV = higher horizontal angular resolution.

 

If you want both to have the same resolution, you have to increase the FoV for the 3440px case until it, too, shows 34 pixels per degree (this happens at ~100 FoV, or roughly ⅓ wider, which unsurprisingly matches how 3440 pixels is about ⅓ wider than 2560 pixels).

 

If you don't want all kinds of anamorphic distortions, the vertical angular resolution will be the same as the horizontal one. This means that for a 3440×1440px display, that vertical resolution only covers ~31°; for the 2560×1440px display, it's ~42° vertical. This is what gives rise to the apparent “cropping”, but if we adjust the 21:9 screen to match the same angular resolution, it too will be ~42° vertical.

 

For same FoV: 3440×1440 → 75°×31° frustrum whereas 2560×1440 → 75°×42° frustrum.

For same angular resolution: 3440×1440 → 100°×42° frustrum whereas 2560×1440 → 75°×42° frustrum.

 

DCS defaults to some given FoV (it's probably not 75°, and it will vary with the module anyway), and this is applied no matter what your resolution. If you want to use extra resolution to show more — height or width — you have to adjust the FoV to keep the angular resolution constant. If you keep the angular resolution constant, things will not be smaller or larger. A 5° tall or wide thing in the distance will take up (in the example above, at 34px/deg) 170px either way.

 

This is something DCS is already capable of handling, live, using the zoom controls. It is also something you can set by editing various view.lua files.

Edited May 19, 2021 by Tippis

[Hiob]

7 minutes ago, Donut said:

I could very well be the dumb one here, but I just don't get it.  It's not what I am seeing and not what examples from other sims/games show.

 

I need pictures/examples..lots and lots, and maybe beer...oh, and donuts. 
 

Thank you to all who are taking the effort to get this understood.

 

the 75 degree are estimated not calculated - it's just an example

when I think about it...it's pretty simple.

Given the monitor hight is the same, it's 60/16*21=78.75

[Hiob]

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to put it in a nutshell - the only thing you have to think about, is the physical width of your monitor (ceteris paribus). This is what determines the fov - nothing else.

Meaning - given the same width, the image of a ultra widescreen will be cropped vertically!

[Donut]

Can someone explain these examples then...

https://youtu.be/vwAY3t6JdPo

 

https://youtu.be/V2lkTv6VqJ8

 

 

[Hiob]

Yes - the ultrawide scenes have a greater fov.

 

The thing is - perhaps DCS doesn't adjust the fov automatically. I honestly don't know in the moment since I carefully adjust the fov for every module via the .luas.

 

Edit: See, what I mean is. When you change the resolution (to match a physical wider screen) there are to options for the software. Either leave the FOV as it is and crop the image OR leave the image hight and change the FOV. In your examples obviously the FOV has changed.

Edited May 19, 2021 by Hiob

[Hiob]

[Donut]

28 minutes ago, Hiob said:

 In your examples obviously the FOV has changed.

 

But not the same way DCS does. In my two examples, everything stayed the same except for an increase in horizontal view.  View distance stayed the same.

 

In DCS, the zoom level changes as well making everything different...view distance to objects inside and outside of the cockpit.  
 

Your drawings do not account for how the scenery changes as well in DCS when FOV is adjusted.

Edited May 19, 2021 by Donut

[Worrazen]

Pfff, ... "Start New Topic" button nuked my post, I'll have to rewrite, recovery didn't work either.

[Raven (Elysian Angel)]

25 minutes ago, Hiob said:

perhaps DCS doesn't adjust the fov automatically

It seems to work just fine to me... This is what my DCS looks like on my monitor (38" ultrawide 3840x1600), and for comparison's sake I took the same setting as Some1 (a Hornet ready for take-off on the runway):

[Hiob]

41 minutes ago, Donut said:

But not the same way DCS does. In my two examples, everything stayed the same except for an increase in horizontal view.  View distance stayed the same.

 

In DCS, the zoom level changes as well making everything different...view distance to objects inside and outside of the cockpit.  
 

Your drawings do not account for how the scenery changes as well in DCS when FOV is adjusted.

 

Zoom and FOV are the same.

I‘ll try to make some shots when home…

I think it‘s only a matter of perception.

 

In which plane and scenery do you like me to make the examples?

[Donut]

5 minutes ago, Hiob said:

Zoom and FOV are the same.

I‘ll try to make some shots when home…

I think it‘s only a matter of perception.

 

In which plane and scenery do you like me to make the examples?

Thank you.

 

Just a simple example...Tomcat sitting on a runway is fine.  
 

I see that FOV and zoom are

the same in DCS, but I think that is what doesn't make sense to me.  In the two examples I posted above, zoom doesn't change.  It's as simple as a wider aspect ratio just equalling more horizontal view.  

[Hiob]

what is the native resolution of your monitor?

[Worrazen]

It's not that simple indeed, I'm probably not going to add much to this right now, as I have my own questions as to how it is and how it should be ...

 

There's two kind of FOV's yes.

 

From traditional games I remember many exposed one and some exposed the other to the user to modify, but under the hood perhaps both were changing based on the other, or not, I don't know that part. I remember is that in every case it would affect both vertical and horizontal space, or I haven't paid attention and I didn't play BF series too much which I know has the less popular FOV setting commonly used.

 

In my casual DCS experience I only know about one FOV that is used for the Zoom controls, I still didn't get into the gut of DCS modding so I guess more could be possible there as others mentioned.

 

I'm not too sure if the FOV should change once resolution changes, in theory you don't change your type of eyes you "just see more" to the side, but seeing more should require more FOV I guess ... that may be because a different FOV value is changing under the hood  ... but perhaps only the horizontal FOV changes.

 

This is kinda interesting as I've never though about it and I'm looking forward to a clarification on this, I'll actually go read through the thread now.

 

 

[Hiob]

This is 21:9 (2560x1080)

and this 16:9 (1920x1080):

Notice, that if adjusted for hight, you have the exact same "zoom-level" (the size of the objects in the scenery is the same) but more view to the left and the right,

and please notice the difference in FOV (obviously my simple math earlier was a little off...probably because it involves trigonometry...)

 

EDIT: to @Worrazen The "Zoom" in DCS does nothing except changing the FOV. You can easily observe that by enabling the stats (strg+pause twice)

Edited May 19, 2021 by Hiob

[Hiob]

35 minutes ago, Donut said:

Thank you.

 

Just a simple example...Tomcat sitting on a runway is fine.  
 

I see that FOV and zoom are

the same in DCS, but I think that is what doesn't make sense to me.  In the two examples I posted above, zoom doesn't change.  It's as simple as a wider aspect ratio just equalling more horizontal view.  

That's what I try to explain to you. Yes it does! You just don't perceive it due to the kind of presentation...

[Hiob]

[Worrazen]

^^ It definitely is different when resolution is taken into account.

 

FOV being adjusted in various games when you're not touching the resolution will affect both the vertical and horizontal screen area and work like the DCS Zoom function does. This is how I always remember it working, irrespective whether the game provides only horizontal or vertical (I'm not sure of a game that you can independently modify both, but perhaps there was a case, but more importantly whether that allowed you to independently modify one FOV without modifying the other, Usually I think it works that when you change one, the other one changes appropriately in some fashion, it may not be necessairly so, I don't know, but when you change resolution and you only see more horizontally, but not vertically, then I think something else must be going on in the background that may have to do with FOVs, and it's different from the behavior of the Zoom function.

 

So here I used UE4 with a camera actor to modify the FOV, they say the FOV is horizontal there. It behaves just like the DCS Zoom Function. But importantly it doesn't have a resolution property, so it's not a display monitor simulation.

 

 

 

Obviously things may be specific to engines and the way they do things for technical reasons, but I'm providing this for comparison if it helps.

 

Which FOV is DCS using there? Because when you use the Zoom, you're changing both the horizontal and vertical areas (FOV's I guess)

Therefore I think the Zoom function must be doing something else besides just the FOV value we see in System Info overlay.

 

EDIT: The WSGF Source Engine FOV Calculator gives both horizontal and vertical FOV values and when changing just one dimension, only one of the FOVs changes, which is what I expected would be happening.

 

https://www.wsgf.org/fovcalc.php

 

So I guess, games that properly support a resolution / aspect ratio, know how to set the default/human-optimal FOVs for that resolution/aspect ratio. So if the FOV wouldn't change ... the aspect couldn't either now I'm realizing if my thinking is correct... because now I tested changing only the Aspect and keeping FOV the same and yes it surely does not reveal any more area in the verticals, only horizontals for the whole range of aspects, because FOV

 

So yes, hFOV and vFOV are independently adjustable and don't have to be in some kind of a balance. It just happens that the ordinary Camera Actor in UE4 does not expose vertical FOV only horizontal. Cinematic Camera Actor is a big more complicated with all of the stuff for making movies so that's why I avoided mixing those things in, because for display monitors we usually don't deal with camera sensor sizes, focal lenghts and such, and DCS probably doesn't either, for the display output at least.

Edited May 19, 2021 by Worrazen

[Hiob]

You can't unlink the vertical zoom from the horizontal - that doesn't make sense.

FOV works not like an optical zoom lense because the focal point doesn't change (take it with a grain of alt - I'm not an optician).

 

Point is - DCS does exactly the same as those youtube examples from @Donut. Except perhaps that you need to adjust the FOV (via the Zoom-button-bindings) on your own.

 

Imagine you stand on a fixed point inside your room and looked out of a relatively small window. When this window changes in size, let's say it's becoming wider, you'll see more (FOV) of the panorama outside without changing the zoom or the distance. But the game doesn't no how far you are away from the window (aka your screen), so you can adjust it. Also, due to the limitations of the world inside a "fixed" screen, games like dcs allow you to change the FOV artificially for your convenience.

 

As I said earlier. A realistic FOV on a single monitor would be 60 degree - give or take - but I bet most players chose to go with somethin between 80 and 100...

[silverdevil]

@Hiob - in your example of a small window. How would you describe the effect by moving closer to the window? Window is same size. but perception of the eye and brain calculates as a bigger window.

[Hiob]

refer to my doodle earlier, when you move closer to the window (or the screen closer to you)…you‘re FOV increases. (by a lot when you come really close)

 

That is why you can (in theorie if you take it very seriously), increase your FOV when moving closer to the screen. Which means, you can see more, but you have to move your head eventually, just like you‘d need to close to a large window.

Edited May 19, 2021 by Hiob

[draconus]

A lot of things were mentioned. Let me explain some bits.

 

Horizontal fov can be independent of vertical fov. They are connected by the aspect ratio. We can input it manually because some monitors are different - their pixels are rectangular, not square. That means 100x100px square is a rectangle when displayed on such monitor. Since the game cannot distinct two monitors with the same resolution - one will have to be corrected by inputting correct aspect.

 

Zoom = FoV. That's easy - you zoom to see something closer, it gets bigger on the screen and then you have smaller field of view.

 

I have not heard of realistic or optimal fov. But there is "real fov". It is the one setting for your eye to screen distance, the screen size and the fov where you can see objects on the screen with the same angular size as in reality, just like it was an empty frame - a window to the world. Unless you sit close to a huge monitor it will be rather low fov - uncomfortable for most simmers. I used around 63 degree real fov with 27" display for over a year and I liked it. Until I went VR realising how bad everything looks on a monitor

 

Hiob might have confused you with changing fov when moving head. He meant the fov measured between viewer's face and the monitor edges. The fov in game stays the same of course. That's why the real fov will only be at one point with the particular monitor. The bigger one will have it further - so you can either sit back or set the higher fov in game.

 

The mentioned youtube videos might have been created from the single video of the wider screen play. The cropping is easy to edit in. Any smart geek would do that. But it's just a showcase of wide display so it's fine.

 

The easiest way to keep the new fov is to set it and save the snap view. The view has to be recalled in every mission then by hitting Enter. The harder way is editing luas for every aircraft - it was done by editing min and max fov, so it's not even one value afair. Don't ask me more on that.

 

Set your fov as you like it - that's my advice.

[Worrazen]

Yes the other in-game FOV adjustment factors in the size of the screen and distance for accurately replicating how human would see if the monitor was part of an HDM. I tried to avoid mixing this in, this may be the "optimal" or "realistic" FOV setting recognized by some, while the other one is regarding the monitor as the eye, both may be valid and work better for different cases but ofcourse no need to agree with me what's optimal.

 

I kinda never played with trying to set the display-as-a-HDM FOV in DCS yet but I did try once in other offtopic games, but it was a long time ago. I just kept using what my eyes were roughly most comfortable with and that was it, but I never liked the console-style 60 or 50 FOV, that made my crazy, those were the times of console ports.

 

With DCS I just never messed with the defaults, particularly because Zoom/FOV is something I would adjust a lot more frequently throughout a session than in any other game/sim.

 

I just never got the idea to do this in DCS, I will sometime.

 

 

On the other hand, if that helps in general.

Edited May 19, 2021 by Worrazen

[Donut]

Thank you all for the examples and in depth explanations.  I understand what FOV is and how it works in DCS.  I just fail to grasp how a wider monitor does not natively display more of an image than a narrower one.

 

I imagine myself looking through the windshield of a car with 1 foot on each side blacked out (16:9), then I look through the same windshield with nothing blacked out (21:9).  The image through the windshield has not changed, I just see more of the view now.  Also, my view of the dashboard would not have changed either.

 

This just does not seem possible in DCS.  

[draconus]

4 hours ago, Donut said:

I imagine myself looking through the windshield of a car with 1 foot on each side blacked out (16:9), then I look through the same windshield with nothing blacked out (21:9).  The image through the windshield has not changed, I just see more of the view now.  Also, my view of the dashboard would not have changed either.

The comparison images and videos can make it confusing. Thing is when you run game on 16:9 there is only that scene rendered, not 21:9 scene and then cut to fit - that would be huge waste of GPU power and would result in the same performance on both resolutions - no game does that. Let's assume that to render the scene on 16:9 75 degrees of fov was used. Now if you move to wider monitor (same pixel count on height) the game can stay on the current fov of 75 - the scene gets bigger but cut vertically to keep the correct aspect - or increase the fov (ex. to 90) to fit the same scene vertically and get more view on the sides. It seems (from the user reports, I have not tested) that DCS does one thing for some modules while the other for other modules. It might depend on the resolution. Either way you are free to change it yourself with one key press - zoom out.