Thoughts on Field of View

[Baffin]

While flying a Spitfire recently, this occurred to me as I played with the "Field of View" and its associated Zoom feature:

As I zoomed to fill the display screen with more "Cockpit", that is, the slower moving presentation of the inside of the airplane, the overall video performance seemed to improve. Consider the huge portion of the screen that's filled with moving objects when banking low over cities... It's obvious that the work required by the rendering system is greatly increased as it tries to "Paint" the huge number of buildings and trees in this situation. Likewise, when panning too quickly with the TrackIR5 headtracker, the rendering demand increases, causing all the common skips and jitters discussed here in our forum. Comparing video performance while flying a a fighter to that while operating a Blenheim bomber supports this hypothesis. The bomber screen has much less "Outside World View" and so displays more smoothly.

Flying at the "Full Size" fighter cockpit (Field of View = 70°) does a couple of things:

First, it fills more of the picture with "Cockpit", and less with the ever changing world outside. I think this improves display performance. (FPS and smoothness)

Next, it more closely approximates the actual size of cockpit elements (Gauges, handles, etc.) by making them larger. On a big screen TV, they can be life-sized.

Finally, it eliminates the unnatural "Fish Eye" effect on the leading edges of the wings which makes them look like they are "Swept" forward. For me, this is a serious shortcoming, especially when viewing videos created and posted here on ATAG.

Of course, this affects game play by altering the available horizon in view as well as distant spotting, according to some players. The work-around is to practice realistic clearing a lot more. (Oooo, my aching neck!)

There's always a trade-off, but for realism and performance, the "Normal" field of view is something to think about.

[BOO]

You are in a growing fan club for this Baffin. I know some players from the BOS forums are extolling the virtues of the fixed view.

The main drawback it that your eyes work better than the game's camera in RL and that there is no peripheral vision.

The most useful compromise Ive seen can be found in videos by the likes of Karaya and Gr00ve (I think) where effective sector scanning by the player is combined with "snapping" to the 30 FOV momentary before returning to the 70 FOV. This is now my preferred method of handing FOVs.

[uranor]

While flying a Spitfire recently, this occurred to me as I played with the "Field of View" and its associated Zoom feature:
...
There's always a trade-off, but for realism and performance, the "Normal" field of view is something to think about.

Eventually, I think that we will all be using VR equipment, where the in-game view is the only thing you can see. At that point, zoom should be eliminated entirely, to provide a fixed view that corresponds to that of the actual airplane.
However, save the few lucky ones that may have huge multi-display arrangements (and even then with a pinch of salt), the screen covers only a part of your field of view, the rest is covered by "real world useless stuff." (i.e. the wall, the desk, etc.) So, no matter what zoom we are in, we are always peering into the virtual universe through a small window (the screen) and cannot have the same situational awareness as in a real airplane. Yes, head trackers help a lot; I could not countenance doing without now, but still limited in a few ways.

I too have conflicting feelings about the zoom: it is unrealistic and I hate the distortions of large FOV, but.. on the other hand, it is a compromise necessary to recover some S.A. (in a non-realistic fashion). At larger FOV you are squeezing more of the virtual universe to fit through the screen viewport, so recovering something that you have lost in the "restricted visualization."

Once VR hardware becomes powerful and flexible enough to be really used for serious simulations (and we are not there yet, in my opinion) we will see the huge leap in quality and realism most of us are waiting for. One of the main reason why VR is not good enough yet, beside frame rates, is how to interact with the virtual world. There aren't sensors that are good enough (accurate, reliable, fast) to allow seamless interaction. I think that we will see a gradual improvement: first we will get VR hardware that can handle the required framerates, then more slowly, sensors may start to be developed. Ideas abound, but implementations are nowhere near the quality required by consumers.

[ATAG_Flare]

I never use the "zoom" feature. Find it hard to always get back to the FOV that I like. Instead I use the FOV 90 key and FOV 30 key. 90 is wider than what you're suggesting, Baffin, but I like it, not too wide that it feels weird, but wide enough to see lots. I use 30 to quickly zoom in to search for contacts, and when aiming, like what BOO says he's seen in videos.

To each their own - everyone will have their preferred FOV settings and I'm glad that we can change it.

[Baffin]

The original post has nothing to do with preferences. It simply addresses the impact of field of view on Computer performance, actual screen object size and the distortion that accompanies "Wide Angle" viewing. I really don't care what other players "Like", and it's not important that others like my preferred FOV. This is not an advocacy thread, but is simply discussing the impact of FOV on technical aspects of the display such as Boo contributed. He has presented an interesting treatment of the impact on peripheral view.

Boo, you piqued my curiosity on this subject, so I reviewed the physical FOV provided by my 55" TV (90°) at my closest distance from the screen. Do you think that matching this with the 90° setting of FOV provides the most optically realistic picture? We must disregard the true peripheral vision outside the 90° panorama since the computer doesn't provide an image out there. (We're not dealing with VR here.) The 70° FOV ignores even more of the unseen peripheral view so is there a formula where we should draw the line on realistic (NOT Preferred) view angle?

I wish I could measure the width of the actual cockpit front windscreen... Then I could simply adjust the Video FOV to make it the same on my screen!

After searching, found instrument panel to be 32.69" wide! I shall try zooming to this on the TV... will report back!

You seem to be our optical expert!

We are all free to use whatever view angle or display device we choose.

EDIT: Reporting back... I've determined (I think) that the Attitude Indicator in a Spitfire is 3.75" outer diameter. In order to make it look "Life Size" on my TV, I use 70° ±2° FOV, but that's on a 55" TV. For this "Realism Nerd", I'm going to try to learn to fly with this setting and I hope my neck can take the strain! The ±2° is easily compensated for by the TrackIR5 zoom axis normally.

I expect my scores to drop, but hey... It's just a video game!

[BOO]

Hello Baffin

The immediate field of view of a human is, as you know, about 70 Degrees and this is what the game replicates most accurately. I have never seen any 2D programme replicate peripheral vision very well. Extending the view outside of this is a compromise and provides a much wider focussed view than a human being is capable of. As such I would have to say 90FOV is not an optimal angle no matter how it is viewed safely.

Regardless of the focussed field of view it unrealistically provides, the 90FOV affects the perceived depth and scale of view too. To see what I mean, take a rule and set your thumbs 34"apart . Now hold it 10" in front of you at chest height. That is very roughly where is the bottom corner of the spit's sliding canopy would sit. If you stare straight ahead note how little of your thumbs are in your main vision and also how close it all "feels".. This more or less matches the 70FOV and perception you seen on screen.

At 90FOV a lot more is in focus but you have also effectively shrunk in size. To put it simply at 70 FOV you sit in the plane, at 90FOV you are beginning to sit on it.


The other big drawback is the distortion in the 3D/2D world with could and framing morphing much more noticeably at a 90 FOV.

FOV is also a fixed aspect of perception no matter what size screen is used. Whilst bigger screens do allow the cockpit scale to be maintained in a wider FOV the effect remains the same. The only thing that has changed is the overall scale. So instead of being aa 1:48 scale pilot in a 1:32 scale plane you are now a 1:32 sale pilot in a 1:24 scale plane.

Of course it is all personal. I prefer the 70 FOV and the sense of being "closed in" that it provides. I also prefer the view to be as undistorted as it can be (although there is still a little). For this though i have to aacept that someone has superglued my eyeballs straight and forward.

On a 55 inch TV the 70 FOV isn't far off being 1:1

Not sure any of that helped or answered your quistions my firend!!

[Baffin]

Hello Baffin

The immediate field of view of a human is, as you know, about 70 Degrees and this is what the game replicates most accurately. I have never seen any 2D programme replicate peripheral vision very well. Extending the view outside of this is a compromise and provides a much wider focussed view than a human being is capable of. As such I would have to say 90FOV is not an optimal angle no matter how it is viewed safely.

Regardless of the focussed field of view it unrealistically provides, the 90FOV affects the perceived depth and scale of view too. To see what I mean, take a rule and set your thumbs 34"apart . Now hold it 10" in front of you at chest height. That is very roughly where is the bottom corner of the spit's sliding canopy would sit. If you stare straight ahead note how little of your thumbs are in your main vision and also how close it all "feels".. This more or less matches the 70FOV and perception you seen on screen.

At 90FOV a lot more is in focus but you have also effectively shrunk in size. To put it simply at 70 FOV you sit in the plane, at 90FOV you are beginning to sit on it.


The other big drawback is the distortion in the 3D/2D world with could and framing morphing much more noticeably at a 90 FOV.

FOV is also a fixed aspect of perception no matter what size screen is used. Whilst bigger screens do allow the cockpit scale to be maintained in a wider FOV the effect remains the same. The only thing that has changed is the overall scale. So instead of being aa 1:48 scale pilot in a 1:32 scale plane you are now a 1:32 sale pilot in a 1:24 scale plane.

Of course it is all personal. I prefer the 70 FOV and the sense of being "closed in" that it provides. I also prefer the view to be as undistorted as it can be (although there is still a little). For this though i have to aacept that someone has superglued my eyeballs straight and forward.

On a 55 inch TV the 70 FOV isn't far off being 1:1

Not sure any of that helped or answered your quistions my firend!!

Thanks, and I agree. After the last post, I edited a revision you may read... By making an instrument dial actual size, the 70 FOV was again validated.

[BOO]

I saw you had reached the same conclusion using less words and more action before id finished my hypothetical musings t!!

[Baffin]

Week one review...

I've been using 70° FOV now for about a week and I'm happily surprised. My scores have not really changed at all as I become accustomed to the "Life Sized" view, and the immersion into the game has improved considerably. I feel much more like I'm really in a plane since I must "Look around" much more to find objects. After engaging the enemy, I feel like it's easier to maneuver for the kill, especially when really close-in.

An observation... TrackIR5 or an equivalent head tracker is a "must" since intense clearing becomes mandatory. No simply flyin' around fat, dumb and happy when you're doing this!

I still get killed just as much, but I have a good excuse since they're not playing "Fair" like I am!

EDIT: Just a note of explanation to our English as a second language players: The comment about playing "Fair" is not intended to be taken seriously. We all play fair in CLoD!

Edit 20180318: I like this view so much now, that my default screen is now 70 degrees...