Major pincushion distortion on screen as default? - VFR (anything with looking out of the cockpit) flying is unrealistic in MSFS by concept?

how did you find these?

Don’t tell me you used the search button?!

I started on this FS with a standard 1080P resolution monitor and even then there was some small distortion at the fringes. By the way, the distortion is both horizontally and vertically. It is just more pronounced horizontally because the monitor is wider and, with a wide screen monitor, it is even more wide. You see exactly the same as the standard width screen but stretched more horizontally.

I don’t understand the reluctance to understand the problem. I am old enough to know about 35mm SLR cameras (now they are digital) and they never had this problem. Even in the panoramic view pictures, they knew about bringing more of the picture to the front to eliminate the distortion we are talking about here.

All that is being asked for is the same thing here. My 3440 x 1440 monitor is 30% wider than a standard monitor. Give me 30% more of the terrain on-screen. Simple.

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I cannot tell you anything else, sorry :wink: search → FOV

simple as this if you don’t like it buy a new monitor or like Portalearth420 Contact your monitor manufacturer for assistance with the amount of effort you put into this just keep playing the sim

I also remember 35mm SLR cameras with wide-angle lenses, and I can tell you they had exactly the same problem.

Note that it has been explained several times how this can be resolved by Asobo: rendering a wider view and adding a reprojection post-process stage that squishes the sides down progressively into a more cylindrical projection. But, very few games implement this, and it would harm performance to do so and make output a bit fuzzier.

There’s already a wishlist item open for this; I believe it’s been linked earlier in this thread.

But you’re probably going to have to live with it as-is, just as you would in competing simulator products.

Pincushion distortion can be (mathematically) corrected, when rendering 3D coordinates of a point in ‘space’ from a virtual camera onto a 2D screen. It’s an additional computation, but it can be done.
https://docs.nvidia.com/vpi/algo_remap.html
https://docs.nvidia.com/vpi/algo_ldc.html

Apparently the entire 3D gaming industry is sticking to an outdated simplified model of translating 3D coordinates onto a 2D screen. It worked sufficiently when the screens were angularly a small ‘window” only in relation to the threedimensional 360 spherical world they projected in 2D. (and the computation power was very limited as well) And it doesn’t work anymore on today’s angularly wider projection surfaces.

Why people get excited about chasing 60+ fps framerates these days (quite pointless, no significant differences in the perceived fluidity of a motion simulation compared to stable 30 fps, particularly in a relatively slow moving virtual world like a flightsim) but cry “it will cost you performance” if we want more realistic projection calculations without major geometric distortions, is a bit of a riddle to me.

My advice to more aspiring virtual pilots for now: only believe your eyes when you see the runway in the MIDDLE of the screen. If you see it on the sides of the screen it looks distorted and closer than it actually is, and you will misjudge your visual approach, your height and your distance.

Brainstorming question: Would it make sense, to add the option in settings to move the eye/camera position in the cockpit (e…g default wide-angle) view further backward? Now it can only be moved sideward and upward.
So the Instrument panel would be the reference and fixed constant, while the zoom is increased for the outside world, and proportionally the distance to the instrument panel increased, so it remains constant in size.
Of course that would be somewhat unrealistic for the position of the pilot’s eyes in relation to the cockpit panels and airframe, but it could be within the current limitations of 3D rendering a good compromise for visual flight, to see enough instruments AND a somewhat less distorted outside visual reference for objects appearing offcenter of the screen (e.g. runways while turning final)?

I guess the POV would then have to be outside of the cockpit behind the plane, for a meaningful difference, so probably not…

You may be new in flight simming, but you are describing a thing we used to call 2D panels, and thankfully we got rid of it.

You may be a seasoned flight simmer, but you got that wrong. I was talking about FOV in relation to a certain instrument panel size. Which requires the POV to move backward if zooming in/making the virtual FOV narrower.

It’s not mapping coordinates that’s so hard, but drawing triangles when straight lines are no longer straight in the output. Hence the explanation of how it requires rendering to a rectangular space with a larger area, then remapping those pixels.

As someone with a 3440x1440 monitor who almost exclusively does VFR flight in the sim, I can tell you this is not really a problem in practice – especially if you’re comfortable panning your view around, just like you would look around with your eye. Remember you also need to look left or right to see the runway position while you’re on downwind – looking always straight ahead isn’t enough.

I strongly recommend just becoming practiced with the mouse, controller, or hat switch to pan around so what you’re looking at is near the center of view.

Some people swear by the “TrackIR” hands-free head tracking system which pans around as you turn your head; I haven’t used it personally, I get a perfectly good experience from panning with the hat switch on my Honeycomb Alpha yoke.

No, this is simply, plainly, factually, mathematically incorrect. It’s not just a matter of devs not trying hard enough or not being clever enough. It just literally isn’t how graphics rendering on a GPU works, at all.

The example you provided is for a pixel shader, not for rasterization. The only thing that will do is take an image that has already been cylindrically projected distort it.

Again, in order to do what you’re asking, the software would need to do the following:

  • Render the screen (with the only available projection there is on a GPU, a rectangular one) 1.5x to 2x wider than normally required
  • Use a warp kernel like the example you provided to “un-distort” the screen into a cylindrical projection

This is not normally done because of the performance and visual quality degradations.

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One could also keep the canvas identical to the screen resolution, but remap the pixels from the inside? Kind of ‘pushing’ them outward, to correct the pincushion distortion? Like a ‘gradual perspective correcting DLSS’.
Minus would be the slight quality degradation happens right in the middle of the screen.
It could be made dependent on the available CPU/GPU power, if its either downsampled (bigger canvas, pixels ‘pushed’ inward) or upsampled (1:1 canvas, pixel ‘pushed’ outward).

With the way MSFS implements cockpit camera views, the pincussion effect at the edges is just part of the problem. The entire view is wide angle. even in the center part of the display. This has some undesirable effects.
The perspective is wrong. Example: you’re on final approach. In reality, if you are one runway length from the near end of the runway, the far end appears half as wide as the near end. In wide angle, the ratio is more like 1/5.
Same problem judging the descent angle during approach. I’ve learned from 3000-odd real world approaches and landings what the apparent angle between the approach end of the runway and the horizon should be. In MSFS, this angle has to appear much less. Fly the glide slope on an ILS (usually 3 degrees) to see the effect.
When flying a pattern, you need to be able to judge distance from the runway during downwind, and when to turn base and final. Real world experience is again useless here. The sluggish response of the C172 model to power and pitch inputs and the pitch overshoots & oscillations make it doubly hard.
On short final, the touchdown point appears to come at you much faster than in reality. Forget about making final tweaks to your approach when you are used to - it’s much too late.
When looking for an airport, it’s sometimes very hard to find visually because it appears much smaller and further away than it would in reality from the same distance. In general, realistic ground reference maneuvers are just about impossible. Try flying precise figure 8’s around a couple of reference points using MSFS sometime!
I often fly to enjoy the scenery. With MSFS, everything looks small and far away. The grandeur of a place like Yosemite is much diminished.
btw: moving the eye closer to the screen just makes the picture bigger - it somewhat fixes pincussion, but does nothing to fix perspective.
If anyone has seriously used MSFS as part of real pilot training, they’ll get some surprises in a real airplane.
I can see reasons for wide angle. I would like to be able to switch between wide angle and normal perspective.

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This is simply false; there’s no such thing as “the view” being “wide angle” “in the center part of the display”.

Perhaps you have chosen the wrong resolution, like 2560x1440 on a 3440x1440 screen?

? No it‘s true. The default cockpit camera perspective is wide angle, adding further general visual distortion to the fisheye pincushion distortion, compared to real life.

Yet the wide angle problem is relatively easy to fix by adjusting the zoom setting in the general options.

The pincushion distortion on the other hand needs a recoding of the 3D-to-2D-mapping by Asobo.

But the comment emphasizes the urgent need for a simple FOV perspective setup tool.
Ask the user for screen width and eye distance to screen. Calculate his real world FOV/zoom setting from it. Would be easy to implement and a big help for all who care about MSFS as a sim, not only a game.

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That’s a different claim, and since your new claim is trivially true and not related to the original claim, well, have fun. :slight_smile:

I don‘t get why you like to argue that, just for contrarian’s sake?
Anyone with eyes can see, how ridiculous the outer sides of a wide screen are mapped to 2D in MSFS.
„all games look like it“
should we care?
Take any airplane.
Look at it frontally or from behind through the drone camera on an ultra wide screen, so that one wing tip is on the left screen edge and the other wing tip screen center.
Now one wing looks twice as big as the other wing. LOL.
Why argue that that can - and should - not be mapped MUCH more realistic, less distorted, on wide screens.
Same with runways looked at from the distance through the cockpit camera etc etc.

I just ran across a camera that does exactly what is being requested at a ski area.

It is a scrolling live 180 degree panoramic view.

Notice there is no distortion all the way to the edge. No fat trees, wide lift chairs, stretched buildings, etc.

So, it can be done. How and when do we get it in the flight sim?

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