Sensation of speed in VR

[etienne1968]

Hi ED,

First and foremost congrats for bringing to military flight simulation enthusiasts such a high level product. The only thing I’d like to report is lack of realism regarding the sensation of speed in VR. I already read some related posts on this forum and some users were not sharing this point of view, pleading it’s a subjective opinion, depending on the FOV and bla bla bla... why such a denial about this true fact ? The point here is not to criticize, nor blame anyone... I guess that DCS community is willing to practice flight simulation in such a manner they are getting close to reality, otherwise video games are available on the market. Reading this forum let me think people are expecting if not a study level flight simulator, at least a very realistic weaponry and onboard systems rendering. Then the visual environment is part of the immersion and especially when it comes to the sensation of speed a low altitude. In real life I fly a liner, and when I’m cleared for a case I type visual approach, I can certify that my downwind leg at 220 knots/ 1500ft is showing something similar to 450kt in DCS. It’s quite a bit frustrating if it is something a good coder could modify in DCS. Some people could argue again it’s my personal opinion as they are amply satisfied as it is. But objectively, a great deal of my friends, actual fighter pilots, flying French  Mirage 2000 and Rafale, are amazed by DCS and commonly say this software is unbelievably close to the real world, except for the sensation of speed totally underestimated. And to give a good point of reference, they say it should be doubled. Some of these fellow fighters are even part of a team using DCS in VR for professional training in the Air Force. I was just willing to humbly share my frustration, thinking DCS is so close to perfection...

regards

[Xilon_x]

I think the sensation of speed is there ok example.

use flat territory put a soldier in it and take a low altitude flight put the outside view and look at your plane in relation to the soldier you will notice that the soldier is moving fast.

try to see the shadow of your plane at low altitude compared to the soldier and you will notice that the shadow is very fast.

 

example look at the shadow of the plane in this real video and try to understand the sensation of speed

 

 

[Quadg]

bla bla bla FOV bla bla bla...

if it feels to fast then your FOV is too narrow. which is a complaint with all VR headsets.

if you use time instead of perception your speed is correct.

if they added a time deceleration function. this could fix your incorrect perception visually.

but then it would screw up your perception of sound.

[Xilon_x]

compared to other DCS simulators it gives you a good feeling of speed.

the difference was noticed between flying at high altitude and flying at low altitude.

the transition from high-altitude to low-altitude flight is important in making you understand speed.

the more detailed the terrain the more you understand at what speed you are going.
 
in DCS to understand the speed try to pass at low altitude next to a building and watch the scrolling of the image.

[sirrah]

3 hours ago, etienne1968 said:

I already read some related posts on this forum and some users were not sharing this point of view, pleading it’s a subjective opinion, depending on the FOV and bla bla bla... 

I've never flown a real fighter jet, so I can't argue over the subject... But, this is a rather immature way of handling other people's opinions and point of view, don't you think?

[etienne1968]

Sorry guys, with all due respect, I don’t talk about any subjective feelings. It’s a matter of fact that speed sensation is like bottlenecked in DCS VR. Virtual pilots not convinced should investigate by inquiring any real military jet skipper. By the way I’m in touch with professional flight simulation imagery designers  (THALES) and I’ve been given the opportunity to experience a private flight sim session. In one word, nothing to be compared with DCS. Common guys, look outside over your shoulder, flying at 600kts/500Ft, it’s a slideshow in DCS. The keyword for THALES simulation division is the sensation of speed a very low altitude to meet their worldwide customers demands. And believe me it’s a struggle for in house engineering.
The only legitimate observation down here to close the debate would be to object the unsustainable development cost, out of reach for a ED. Moreover a professional flight simulation imagery is powered by a hardware suite costing  tens of thousands USD, which is out of reach for a public consumer market as well. It could be the final point if some consumer market products were not doing better in VR. I refer to Aerofly FS2 for instance, undoubtedly  bringing to my eyes a more convincing sensation of speed  in 3D environment like Manhattan or downtown Chicago. That’s why I opened this topic as a desperate call to catch ED core development team attention on this subject. I mean, out of twelve, not even a single of my fellow fighter pilots experiencing DCS in VR at home was satisfied as they were overflying the carrier at 500kts. All of them were claiming this is a critical point to be focused on. And by the way I’m a daily flyer and from my Airbus A320 cockpit, what I visually sense at 250KTS/3000Ft in real world is matching what DCS bring to my eyes at 500KTS. This is the undeniable truth. I’d rather be explained by Waggs or Big Newy that unfortunately DCS aging source code is outdated and limited, than being fooled by some people pointing out a dumb subjective misperception. And once again I’m neither blindfolded nor narrow minded when I’m objected any kind of technical explanation pertaining FOV, GOPRO like shooting tending to exaggerate the speed perception and so on. I do not question time equation, matching perfectly the ration distance/speed in DCS. but between two geographical poins, the rate of visible images per second for a given speed is not matching reality.  Just trust your eyes, fly for real and make truthfully an objective opinion.

regards

[Expert]

2 hours ago, Quadg said:

bla bla bla FOV bla bla bla...

if it feels to fast then your FOV is too narrow. which is a complaint with all VR headsets.

if you use time instead of perception your speed is correct.

if they added a time deceleration function. this could fix your incorrect perception visually.

but then it would screw up your perception of sound.

That's correct

[Expert]

10 hours ago, etienne1968 said:

Hi ED,

First and foremost congrats for bringing to military flight simulation enthusiasts such a high level product. The only thing I’d like to report is lack of realism regarding the sensation of speed in VR. I already read some related posts on this forum and some users were not sharing this point of view, pleading it’s a subjective opinion, depending on the FOV and bla bla bla... why such a denial about this true fact ? The point here is not to criticize, nor blame anyone... I guess that DCS community is willing to practice flight simulation in such a manner they are getting close to reality, otherwise video games are available on the market. Reading this forum let me think people are expecting if not a study level flight simulator, at least a very realistic weaponry and onboard systems rendering. Then the visual environment is part of the immersion and especially when it comes to the sensation of speed a low altitude. In real life I fly a liner, and when I’m cleared for a case I type visual approach, I can certify that my downwind leg at 220 knots/ 1500ft is showing something similar to 450kt in DCS. It’s quite a bit frustrating if it is something a good coder could modify in DCS. Some people could argue again it’s my personal opinion as they are amply satisfied as it is. But objectively, a great deal of my friends, actual fighter pilots, flying French  Mirage 2000 and Rafale, are amazed by DCS and commonly say this software is unbelievably close to the real world, except for the sensation of speed totally underestimated. And to give a good point of reference, they say it should be doubled. Some of these fellow fighters are even part of a team using DCS in VR for professional training in the Air Force. I was just willing to humbly share my frustration, thinking DCS is so close to perfection...

regards

If the developers have done things in scale, trees, houses etc ... using the correct formula Velocity = Space / Time, we should have the same perception as reality but as you say this does not happen and I believe you, in fact it does not happen for two reasons .

The scenario does not have the same details as in the real world and therefore the low altitude flight seems slower because due to the fewest static points of visual reference.

The fov. The fov plays a huge part in the perception of speed, this is a fact.

So unless the scenario is rich in details, and unless you use a VR viewer with + 200 ° of fov, it is impossible to have the same perception of the real world.

Edited January 31, 2021 by Expert

[Taz1004]

This is actually related to this 

One of the topic that comes up from time to time.  But it has more to do with level of detail than FOV.  In Caucasus, some gaps in concrete runway is twice the width of my A10C's front wheel.  And potholes size of a person everywhere.

Most of the trees in the cities are way too large.  Many of them tower over 5 story buildings.  Of course your sense of speed will be halved if you fly over trees that are double the size.  ED obviously did this for performance reason.  To use less trees to cover the same amount of area.

 

 

Syria I think done better job of scale and does yield better sense of speed.  Which is also why it's heavier.  Smaller but more detail to cover the same amount of area as Caucasus.  I think this video is fairly close to the real footage posted above.

 

Edited January 31, 2021 by Taz1004

[Mars Exulte]

''Sensation of speed'' is closely tied to FoV, you have zero peripheral vision with a VR headset. It's just this side of wearing cardboard tubes on your face. So it's going to be off to start with until that improves.

 

There is some argument to be made regarding scale of some objects, with varying levels of credibility, but there are more maps than just the antiquated Caucasus map. Go to Nevada, hardly ANY trees, you're just flying over scrub brush and mountains. The FoV is still the driving factor in this sensation.

 

At the end of the day, it's a game with a close approximation of reality, but it's not 100% and isn't gonna be anytime soon.... although the new clouds will be a big step in that direction

Edited January 31, 2021 by zhukov032186

[wilbur81]

5 hours ago, etienne1968 said:

Hi ED,

First and foremost congrats for bringing to military flight simulation enthusiasts such a high level product. The only thing I’d like to report is lack of realism regarding the sensation of speed in VR. I already read some related posts on this forum and some users were not sharing this point of view, pleading it’s a subjective opinion, depending on the FOV and bla bla bla... why such a denial about this true fact ? The point here is not to criticize, nor blame anyone... I guess that DCS community is willing to practice flight simulation in such a manner they are getting close to reality, otherwise video games are available on the market. Reading this forum let me think people are expecting if not a study level flight simulator, at least a very realistic weaponry and onboard systems rendering. Then the visual environment is part of the immersion and especially when it comes to the sensation of speed a low altitude. In real life I fly a liner, and when I’m cleared for a case I type visual approach, I can certify that my downwind leg at 220 knots/ 1500ft is showing something similar to 450kt in DCS. It’s quite a bit frustrating if it is something a good coder could modify in DCS. Some people could argue again it’s my personal opinion as they are amply satisfied as it is. But objectively, a great deal of my friends, actual fighter pilots, flying French  Mirage 2000 and Rafale, are amazed by DCS and commonly say this software is unbelievably close to the real world, except for the sensation of speed totally underestimated. And to give a good point of reference, they say it should be doubled. Some of these fellow fighters are even part of a team using DCS in VR for professional training in the Air Force. I was just willing to humbly share my frustration, thinking DCS is so close to perfection...

regards

What do you want? Do you want millions more pieces of tiny ground clutter, smaller/more trees and bushes, etc going by your view?.... then you'd have to accept the 6 fps performance that would come with the added detail. A simulation like DCS, doing SO many different things, is a series of hundreds of compromises. You want a sense of greater speed? You need a whole different level of real-world objects of tiny size going by your field of view. The technology to produce this level of scenery detail AND avionics, physics, weather, ATC, sound, explosions, ground troops, naval vessels, wingmen, AI, smoke trails, contrail zones, flight models, etc. ALL while playing at 60 FPS will be available to you in the year 2050 a.d. and beyond.

 

 

[Taz1004]

11 minutes ago, zhukov032186 said:

''Sensation of speed'' is closely tied to FoV, you have zero peripheral vision with a VR headset. It's just this side of wearing cardboard tubes on your face. So it's going to be off to start with until that improves.

 

There is some argument to be made regarding scale of some objects, with varying levels of credibility, but there are more maps than just the antiquated Caucasus map. Go to Nevada, hardly ANY trees, you're just flying over scrub brush and mountains. The FoV is still the driving factor in this sensation.

 

At the end of the day, it's a game with a close approximation of reality, but it's not 100% and isn't gonna be anytime soon.... although the new clouds will be a big step in that direction

 

 

FoV (Field of View) is often mixed up with Focal Length.  Because in "camera", changing focal length would change FOV as a "result".

But FoV is only talking about how much you can see in front of you and focal length is changing the lens distortion like if you're wearing glasses or looking through binocular.  Focal length would change sense of speed.  But not FOV.  If I'm driving at 70mph and cover left and right side of my eyes with my hand, it does not change my sense of speed.

 

And in VR, focal length is supposed to match that of real life and can't be changed.

Edited January 31, 2021 by Taz1004

[Mars Exulte]

1 minute ago, Taz1004 said:

If I'm driving at 70mph and cover left and right side of my eyes with my hand, it does not change my sense of speed.

  There's a lot more that goes into it in RL than simply focal length OR FoV, but the only one we actually have control over is FoV in a game. For example, a lot of physical sensations of motion go into feeding your perceptions, too, which we have exactly zero of. All those tiny corrections you make, every little bump, and the inertia conveyed with each. Your entire peripheral vision, and yes, to an extent your ''focal length'' as far as looking inside vs outside down the road but your peripheral vision is a major part of that. Look in your floorboard and you can still see the terrain passing you by in your peripheral vision, thus you still have the ''feeling of speed''.

 

1 minute ago, Taz1004 said:

And in VR, focal distance is supposed to match that of real life and can't be changed.

  I really don't know enough about how it works in VR to comment. I was told by somebody on here it was approximately 1.5-2 meters (I don't remember the exact number), equivalent to the average distance a person sits from their monitor. Obviously, that's not gonna be adjustable.

 

But like I said already, this isn't real life, it's an approximation, and there's lots and lots of corners cut in this stuff.

[SharpeXB]

This topic doesn’t make sense. Are you saying the airspeed of the aircraft in DCS is wrong? No. Your perception of this is what’s affected by VR headsets, IPD settings, FOV etc. so it’s all on the user side, ED can’t control that. 
FOV has a huge effect on this perception and sim racers try to dial this in precisely. Try zoom viewing in and out while taxiing and see. 
VR players are looking through a blurry scuba mask at lower levels of detail and dealing with reprojection artifacts and stutters. That’s what affects your perception. 

Edited January 31, 2021 by SharpeXB

[Xilon_x]

9 minutes ago, SharpeXB said:

Questo argomento non ha senso. Stai dicendo che la velocità dell'aereo in DCS è sbagliata? No. La tua percezione di questo è ciò che è influenzato da visori VR, impostazioni IPD, FOV ecc. Quindi è tutto sul lato utente, ED non può controllarlo. 
Il FOV ha un enorme effetto su questa percezione e i sim racer cercano di comporlo con precisione. Prova a ingrandire e rimpicciolire la visualizzazione durante il rullaggio e vedere. 
I giocatori di realtà virtuale stanno guardando attraverso una maschera subacquea sfocata a livelli inferiori di dettaglio e hanno a che fare con artefatti di riproiezione e balbettii. Questo è ciò che influenza la tua percezione. 

 

 

yes you are right the speed is good it all depends on the perspective with which you look at the objects.

Maybe we need to make some changes in the map of the Caucasus to adjust the size of some trees more than 5 floors high in a building.

Another problem to be added to the map of the Caucasus is the distinction between urban center (city) and countrys.

example in this photo I am at the SENAKI airport in front of my view there is the city of SENAKI.
Can you figure out which city is? Did I see only countryside and trees?

 

 

 

[SharpeXB]

58 minutes ago, Xilon_x said:

Maybe we need to make some changes in the map of the Caucasus to adjust the size of some trees more than 5 floors high in a building.

Are you saying ED modeled the trees the wrong size? I think they know what the Caucasus looks like IRL

[randomTOTEN]

2 hours ago, Taz1004 said:

FoV (Field of View) is often mixed up with Focal Length.

Not when the projection display remains fixed. If you change FoV but do not change your physical display a change in Focal Length is mandatory.

[Taz1004]

9 minutes ago, randomTOTEN said:

Not when the projection display remains fixed. If you change FoV but do not change your physical display a change in Focal Length is mandatory.

 

I already mentioned that.

Quote

Because in "camera", changing focal length would change FOV as a "result".

 

But we're not talking about camera lens here.  FOV in VR literally means viewable angle versus Focal Length is distortion of the view.  They are completely separately controlled in game engine unlike a physical "camera"

 

Plus, I can change physical IPD of my Vive Pro from 60mm to 75mm.  Effectively changing Field of View angle.  I get very tunnel vision with 60mm but makes no difference to "sense" of speed.

Edited January 31, 2021 by Taz1004

[etienne1968]

1 hour ago, SharpeXB said:

This topic doesn’t make sense. Are you saying the airspeed of the aircraft in DCS is wrong? No. Your perception of this is what’s affected by VR headsets, IPD settings, FOV etc. so it’s all on the user side, ED can’t control that. 
FOV has a huge effect on this perception and sim racers try to dial this in precisely. Try zoom viewing in and out while taxiing and see. 
VR players are looking through a blurry scuba mask at lower levels of detail and dealing with reprojection artifacts and stutters. That’s what affects your perception. 

 

See no offence buddy but this topic makes sense to me and is not as irrelevant as you think. Disregard the topic if it is bothering you in any way. I respect your opinion and therefore expect mine to be respected in return. One more time it is a true fact that the sensation of speed is realistically rendered flying Aerofly FS2 in VR, and this software it is way much less ambitious than DCS. And If you had read carefully my post, you would have noticed that I do not question the airspeed of the aircraft as a parameter itself... The sensation of speed is not properly rendered whatever the detail of clutter is displayed. And when I fly in VR with my HP reverb at a given FOV, with almost all sliders maxed out, boosted by my RTX3090/I9 9900K, I persist to say it is frustrating as we are so close to perfection.

No doubt soon or later, computer technology will be matching expectations with no compromise, unless it is already feasible today. Now if you are satisfied as it is, perfect enjoy.

[nessuno0505]

Maybe it's just a matter of frame rate: neither a 9900K+3090 can render DCS VR with a reverb at a decent frame rate, FS2 is a lot more simple simulator. Maybe you see stutter and you say speed is not right. Look at some DCS low-level flying on a monitor in a youtube video (there are plenty of them): when I do it I see a super-fast, super smooth speed sensation, something far away from what I can achieve in VR with my 2070 and Rift s. It's not a problem of software coding, IMHO, it's a problem of frame rate: in VR it's impossible to achieve. I plan to buy a 3080 (if it will be available in stores, sooner or later I hope) and keep my Rift s, to see if I can reach in VR a frame rate close to those flat screen youtube videos. With a reverb, I think it's just impossible, whatever the CPU and the video card.

Edited January 31, 2021 by nessuno0505

[etienne1968]

3 hours ago, Taz1004 said:

This is actually related to this 

One of the topic that comes up from time to time.  But it has more to do with level of detail than FOV.  In Caucasus, some gaps in concrete runway is twice the width of my A10C's front wheel.  And potholes size of a person everywhere.

Most of the trees in the cities are way too large.  Many of them tower over 5 story buildings.  Of course your sense of speed will be halved if you fly over trees that are double the size.  ED obviously did this for performance reason.  To use less trees to cover the same amount of area.

 

 

Syria I think done better job of scale and does yield better sense of speed.  Which is also why it's heavier.  Smaller but more detail to cover the same amount of area as Caucasus.  I think this video is fairly close to the real footage posted above.

 

 

I understand your point but persist to say the sensation of speed is unproperly rendered as you must achieve something like 600Kts to obtain this result. And flying that close to the ground at 500 or 600Kts would give you way much more sensation in real life for sure. The usual speed flown in real life as shown on the real footage is around 450Kts. Most of the time, if you pay attention to ED youtube ads, boasting a new scenery or module, very low altitude cities overflying is always shot at 700Kts in the HUD. So they know they have to boost the speed rendition to be more immersive, impressive and then realistic... 

[Taz1004]

8 minutes ago, etienne1968 said:

I understand your point but persist to say the sensation of speed is unproperly rendered as you must achieve something like 600Kts to obtain this result. And flying that close to the ground at 500 or 600Kts would give you way much more sensation in real life for sure. The usual speed flown in real life as shown on the real footage is around 450Kts. Most of the time, if you pay attention to ED youtube ads, boasting a new scenery or module, very low altitude cities overflying is always shot at 700Kts in the HUD. So they know they have to boost the speed rendition to be more immersive, impressive and then realistic... 

 

Obviously missed the point.  That same 600kts at same altitude in Caucasus vs Syria will give you different result.  Was the point.  I didn't mean Syria is exactly same as that video or perfectly realistic.  I meant it is "closer" than Caucasus due to better scaling and more detail.

Edited January 31, 2021 by Taz1004

[etienne1968]

3 hours ago, wilbur81 said:

What do you want? Do you want millions more pieces of tiny ground clutter, smaller/more trees and bushes, etc going by your view?.... then you'd have to accept the 6 fps performance that would come with the added detail. A simulation like DCS, doing SO many different things, is a series of hundreds of compromises. You want a sense of greater speed? You need a whole different level of real-world objects of tiny size going by your field of view. The technology to produce this level of scenery detail AND avionics, physics, weather, ATC, sound, explosions, ground troops, naval vessels, wingmen, AI, smoke trails, contrail zones, flight models, etc. ALL while playing at 60 FPS will be available to you in the year 2050 a.d. and beyond.

 

 

What do I want, Wilbur81 ? just a kind word of ED team, saying we know that and soon or later technology should be responding to that matter. Or something like, yes it is actually technically speaking feasible but not considered as it would be too costy or complex to workout the core software or whatever. Needless to be the spear head of ED, I just express my personal wish list, shared by many others. And by the way, DCS isn't only a video game anymore as they are targeting a professional market, my national Air Force being a client.

regards

[etienne1968]

8 minutes ago, Taz1004 said:

 

Obviously missed the point.  That same 600kts at same altitude in Caucasus vs Syria will give you different result.  Was the point.  I didn't mean Syria is exactly same as that video or perfectly realistic.  I meant it is "closer" than Caucasus due to better scaling and more detail.

 

You are right about scaling and Syria map with regards to Caucasus. And I'm on the same page regarding the level of detail or ground clutter as a factor affecting highly the sensation of speed. But actually, the sensation of speed in VR is unfortunately not even close to reality. And surely for an optical limitation reason, this is the trade off for VR users compared to 2D monitors users... 

[Xilon_x]

F16 low flight hight speed