RealDCSpilot

Yeah, on one side it's cool to have the option to modify. But this is also another indication that DCS might do a little sidestep here and doesn't follow the rules. Personally i do not use it, this should all be managed by the OpenXR API. It takes the value you mechanically set in your headset and reports it to the game which should adjust it's camera rig accordingly.

Well, here the moon is only an indication that something is off. Spotting of distant objects is problematic in general in VR. FOV not set right could act as a problem amplifier. Sadly we can only change IPD but not FOV to check.

IPD should always be on your personal eye distance. This setting changes the world scale as perceived from a normal adult human to a toddler or a giant. Everything close to you in the cockpit will get bigger or smaller but it doesn't do anything to size perceived for very distant objects. Which makes sense and i also double checked if there is anything wrong with it.

That question kept me thinking and i got the idea for an experiment. Highly inaccurate of course without knowing on what values the cameras in DCS truly operate. There is this tool which is pretty famous for being used measuring your VR HMD's optical FOV in a calibrated space. https://knob2001.itch.io/testhmd To get your horizontal FOV measured, you have to stare at the center of an image with two red bars left and right. Then you move those bars further and further into your peripheral vision until you can't make them out anymore. My current HMD gives me a result of 110° (depends on personal face shape and eye position). So i did a simple test in DCS. Prepared a date and time with a full moon close to the horizon, centered my heading on it and started turning sideways until i reached 55° more (233° -> 288°). Always kept the yellow cross of the fixed mouse cursor in the center. The moon was leaving my field of view at 292°. This basically means that DCS renders a FOV of 118° on my headset with 110°. Would be nice if someone else could test this too on his end... On top of that, i talked to a former Tornado WSO which also uses VR in DCS too and gave him the test mission. He said, from his memory, the moon definitely appears to small in DCS. By 30-50%.

Not if you keep your head on an exact fixed position with a fixed distance to the screen and have set up the correct FOV for that distance. May not be practical in most cases because you have to cut away a huge area. But a 3D world on a 2D monitor only is always a way bigger abstraction than VR. A half dome screen would be best.

Man, you are really starting to waste my time. Optical FOV is fixed in every HMD. The screen space is also fixed - the rendered window on each display per eye. Pixels don't play a role here. How much perspective you cram into that fixed space is happening on the software side, in the VR camera rig. The VR spyglass zoom demonstrates this very well, but with a way to big value for this purpose here. Did you never wonder why when you look around in the cockpit, the pilot model's feet look a bit tiny? Or the seat? Despite you have your IPD correctly dialed in in the VR HMD? That's a wrong FOV.

Quad view and eye tracking...

No, not entirely. It would have the most impact on everything that is rendered at infinity (skybox with moon patch on top and hud). The closer something is to the camera, the less it would be affected. And i'm talking about a correction of 1-2° only. Let's say 2° less and the Moon + HUD will be rendered a bit bigger while still holding the correct measurement. Here is something fresh from the night sky: As soon as i stepped on the balcony i was reassured that something is wrong in VR in DCS. The real moon appears so much larger for the bare eye than it does in VR for the "bare" eye. Of course this is all crappy cellphone photography, with no scientific value with stretching out arms and so on... The camera also doesn't have the dynamic range the human eye has. This is a montage, just for visualization: I'm much more sure now that the whole thing is a FOV issue in VR. Decreasing the FOV angle by a couple degrees would also impact spotting distant objects in the skies, this is a problem in VR for years now. It would definitely improve it.

??? What? How? I hope you know about image pre-distortion for VR HMD optics and that a screenshot of a display panel in a VR headset like this: is the same like this: Setting a couple degree more FOV would only add to an effect like concave lenses like in correction glasses for short-sighted people. Reducing a couple of degrees would have an effect of convex lenses like for far-sighted people. Inside the headset you wouldn't see much of a difference because everything looks related to each other and 6-dof movement isn't affected at all. What i'm trying to tell you the whole time is that we are looking at a "concave lens" effect all the time, that's why the moon looks smaller in VR than in real life.

Okay, you didn't get the connection about FOV out of this. Let's get this more clear, this is the DCS VR camera rig: For the spyglass zoom functionality, they manipulate the whole rig. It's a linear interpolation for about one second from a start FOV value to the much more narrow FOV value. They might even translate the IPD too for this. I've never seen this in any other VR game. While it works, it might have a slight flaw. The start FOV value which might be a couple of degrees bigger than it should be. While IPD is exposed and changes world scale, especially the appearance of very close objects, FOV has more impact on the appearance of Objects and especially on those that are extremely far away. ... or any other exposed FOV setting does only apply to monitor usage. For VR it does nothing. There might be a .lua somewhere, but i couldn't find it yet.

As i'm trying to point out all the time, it's about how big the moon appears in VR. I never use DCS on a monitor. I still think that FOV for each eye could be the source of the moon being smaller perceived than in reality. Unfortunately, i can't change the FOV per eye anywhere. There is "VR spyglass zoom" which does that, but it only toggles from a min to max value and back if i hold the button. Can't bind it to an axis, which would help a lot in this case here.

It's actually three different sims in those images. And no, i will definitely not "thrust" my eyes. Well it's the oldest one in the comparison. Have to give it some slack here. Did that, the hand object is touching the cockpit frame arc. And yes, of course a glove makes the fingers a bit bigger. But i can't bring any other reference object into the game. Well, isn't that interesting...? From all sims it actually gives me the best result how i can see the Moon in real life (size and darker surface details).

Alright, let's see... Hmmmm... and another two other sims examples... So they are all wrong?

Guess what, i can do this in VR. And as expected, it's to small. Needs to be 2x bigger i guess... As i already said, i would expect the size of a pea, not a pinhead.

I didn't say that. That was freehand. But i can relate to what he said. ED makes a lot of changes under the hood without mentioning them in the changelogs. Night lighting is a very good example, it was broken for years. The last time i remember having full moon as main light source and realistic ground illumination working correctly was ~2019. Then it got broken again and the moon was only a sprite in the sky and the ground always dark as hell no matter what. Especially this was problematic for LCD VR headsets because everything looked extremely dark and i stopped doing night missions at that time. This was going on for years. Now, since a couple of months, night lighting did have a really nice comeback and it seems to work well across all maps now. And i also got a "new" OLED VR headset since last week which makes doing night missions really enjoyable again. But well, the size of the moon is off... As perceived through my VR headset. What makes me confident is -> i'm an old fart. I've simply seen many full moons in my life. And can't do a scientific measurement to compare FOV with other sims. Because that would need the exact same 3D object being looked at from the exact same distance in both simulators. Don't have the right tools for that. No.

About the "hard data"... he measured with using a scale "inside the problem". The coin will always have the right diameter in millimeters, yes... but that seems not to be the problem here.

@buur Do you even have a VR headset? You'll never understand the problem if you only know DCS as a flat game. For info, i just did a test in the F/A-18E in the other flight sim. Made a screenshot from the right eye and yes, DCS is rendering a higher FOV per eye for the same VR headset which now really smells like the source of the problem. "More perspective" is rendered in the same space which leads to objects appearing smaller than perceived in reality.

So i tried to match a real life foto to a screen capture of what's rendered in the HMD... F/A-18 at 35000 feet. I definitely would expect to see a moon diameter nearly twice as much as currently rendered in the HMD. @Czar66 Yes, you brought up the keyword. It might be a slightly too large FOV per camera that render each eye for the VR HMD. If any of the other parameters are correct, this is probably the only option that produces this issue. It basically squashes the image and is hard to spot because you can't bring any real object into the virtual world to reference. Question is, if that FOV value is accessible somewhere for us to check.

You still seem to not get it. This is a reference position. This is exactly where the head is. At a distance to the frame that does make sense. The screenshot is me in the AH-64 cockpit, simply looking up in the sky. In other sims the moon is also showing up bigger. So they are all wrong and DCS is the only one who does it right? More real life impressions: https://www.facebook.com/MentourPilot/photos/a.963992186989923/3228398517215934/?type=3 https://www.facebook.com/airlinkairlines/posts/a-full-moon-over-the-tasman-at-3am-captured-by-rhys-on-a-flight-in-our-cj3-from-/1492184397833072/ https://www.reddit.com/r/aviation/comments/9j9psi/snapped_this_shot_of_the_full_moon_during_the_mid/

Next full moon is in 4 days, i hope for a clear sky. The top window frame of the AH-64 is a good reference frame for proportions. It is quite close to your head and now look how tiny the moon is in proportion to that window. Maybe you'll need to go outside too from time to time. Or at least, look out the window. Something is off. However, i'm kinda sick about running after problems in DCS. The latest patch introduced a new bunch of bugs again. They should start getting their <profanity> together. The 15th year is one of the worst so far. They are really loosing it. Here is the same screenshot with boosted brightness:

See title. I have bound all mouse buttons to my HOTAS, can't use them anymore in spawn selection since yesterday's patch. DCS main menu - works. DCS multiplayer menu / server list - works. Entered server, spawn slot selection - not registering. Spawned in cockpit - works again (on map, in cockpit).

Then there must be a world scale issue in VR in DCS. And someone at ED was asking himself the same question and started tinkering with moon size over the last patches. It should look more like a pea not like a pinhead.

Thanks, started with checking different values. This picture looks right (because reality). What i see in DCS atm looks like more like a far more distant planet. https://www.pinterest.de/pin/another-day-at-the-office-with-an-excellent-full-moon-scene-on-a-quite-clear-night-awesome--547961479648671372 here comes another one: https://www.pinterest.de/pin/bright-moon-on-night-flight-in-crj700--573294227540476932/ 0.52 degree is mathematically correct, but what DCS does with it in it's code and what we get as a result not. Take the AH-64 cockpit frame into account not the HUD.

I'm strictly playing in VR and this is my observation. IRL everytime at full moon it shines through my window, in my bare eyes i see it so much larger than the current scale in DCS. Check the other flight simulator even there the moon is much bigger than what we now have. Don't focus on numbers only use your eyes.

With the latest patch it's to small now...