5K+ review for DCS

Introduction
15 months ago I backed the Pimax 8KX. Following that I purchased an Odyssey as in “interim” HMD for which I posted a review here:

Samsung Odyssey review - Virtual Reality - ED Forums. In essence, I wasnt impressed and went back to my 65" 4K TV for DCS (Panasonic 65AX802b) + TIR. Unfortunately, I couldnt hack the massive drop in visual quality and clarity. I was however, under no doubt, that VR was the future for flight simming, if not gaming in general.

Last week I finally received my 5K+! The following day I put an order for a 2080ti since it was clear to me before even trying it that even a 2080ti would struggle to deliver acceptable frame rates.

Ive been using the 5k+ for close to a week now and feel ready to post initial impressions. This review is really geared to users like myself that have wanted to get into VR but weren’t quite ready to give up the sharp image of a normal display. Im sure current vive, rift and SO users would probably consider my settings too high given the extra pixels the 5k+ is pushing out but ive approached things somewhat differently. Instead of finding an acceptable framerate and then seeing how far I can push the graphical settings ive tried to find the minimum visual quality that I would consider acceptable to make the switch and then see what FPS I get. I love how DCS looks. Its beautiful in certain light conditions and the experience is even more amazing on a 4k big screen. Basically, im not an easy customer for VR.

Hardware: 8600K@5.3ghz, 32gb 3200mhz ram@CL14, 1080ti/2080ti both at 2ghz.

Build quality and comfort
Build quality is actually quite good. The headset feels quite sturdy despite being very light. It came well packaged and generally everything looked and felt good. The headstrap is functional but im sure something like the Vive DAS would feel alot better. Pimax are developing their own DAS. Personally im glad it doesnt have integrated headphones. The SO sounded pretty terrible and were not removable. Even an entry level Sennheiser would sound alot better and be more ergonomic. I use my own.

Im not a fan of the megatron look with the blue light. We look dorky enough playing flight sims.

Installation and software tweaking
No problems here. I installed SteamVR and then installed the Pitools software and it was instantly recognised together with the lighthouses. I had huge issues with the SO with WMR software and W10 updates. Thats probably all fixed now but im glad I had no similar issues with the pimax.

Note: For DCS you must check use parallel projections otherwise you get a double vision effect. This is a workaround for “older” titles but eats away at FPS. Assetto Corsa for example doesnt require it and sits quite happily at 90fps!

There are essentially 2 quality settings you can control outside of DCS. The Pitool Rendering Quality (default 1.0) and the SteamVR application resolution (default 100%). Im not entirely sure of the interplay between the 2 and how it works with the PD setting in DCS. But after alot of trial and error I settled on Pitool 1.25, SteamVR 100% and DCS PD 1.0. This gave me perfectly readable cockpits far beyond what I experienced with the SO.

Within the Nvidia control panel I changed power management to Prefer maximum performance and VR pre-rendered frames to 3. This last setting is particularly important since it removes many of the judders that you might get with low fps.

FOV and sweetspot
This is whats really impressive. The FOV is just great. Its not quite life like, more like looking through a scuba diving mask, but it really sets it apart from the competition. Even more importantly is the size of the sweetspot. If theres one thing that makes this HMD totally unique its the fact that the FOV is huge and most of it is perfectly focused with good clarity without even trying. I had huge issues with the SO trying to dial in its minuscule sweetspot. It felt like trying to read a map by looking through a monocular telescope. By contrast the 5k+ you just put it on and most of your vision is perfectly clear and in focus. I think this explains why I had no nausea with the 5k+ despite jumping in to the 104th almost immediately. IPD adjustment is via a scroll wheel with an OSD.

Distortion
In small FOV ~125 degrees – No distortion.
Normal ~150 degrees - Very minimal at the edges. Closest I can describe it like the seeping in of water at the edge your mask while scuba diving. Noticeable at first but doesn’t detract from the experience.
Large ~170 degrees – slightly more at the edges.
I preferred Normal FOV throughout my testing. There was minimal FPS difference between any of the FOV settings.

Clarity, definition and colour
Clarity and definition were far better than my experience with the SO. Everything in the cockpit is readable without zooming or straining your eyes. This, together with the sweetspot, in my opinion is the game changer. Spotting planes is doable but visual IFF is hard till they get closer. The colours are washed out compared to a normal display. I don’t remember the SO colours in comparison too well since a lot depends on time of day and season etc. Most people have said colours are better on the SO. OLED vs LCD. Supposedly the 5k+ is tuned to a colder colour palette and that this will be user selectable cold/warm in future updates. DCS gamma setting helps a little in this regard but I wish this was better. To be fair, none of the HMDs are in any way comparable to a good display in terms of pure visual quality.

SDE and Gods Rays
The SDE as I understand it is still just about perceptible although I can make out the pixel pattern against a light coloured uniform background if that makes sense. For example the pixel pattern is visible against a clear blue sky but not so against the terrain.

No God Rays.

Tracking
Fine. I use steam base stations I picked up on ebay 2nd hand.

Combat effectiveness.
To my surprise with very little adjustment time I was able to jump on BF and the 104th and fly combat missions effectively as a Lead and a wingman. I cant say my K/D ratio suffered due to VR. I fly modern jets mostly so visual IFF and spotting are less important. The systems help a lot. Visually I can quite easily maintain a 6-8km spread. If I were into WW2 combat I’d have more of an issue with the poorer medium range distance spotting compared to a monitor. The little time I spent in Helis was quite enjoyable. Overall im pleased.

FPS
Again I must reiterate that I’ve deliberately set the bar quite high. The 5K+ pushes out 4815x4113 pixels per eye with a pitools setting of 1.25 and SteamVR 100%. Pitools 1.0 and steam VR at 60% (recommended settings) push out 2984x2549 pixels and its still perfectly playable. What can I say? I like pretty.

I use the following graphical options:

All benchmarks used the instant action missions. fpsVR.

1080ti|2080ti.

Caucasus

FPS, GPU frame time(ms), GPU usage(%), CPU frame time(ms)

F18 instant action
4v4 32|40 26|19 78%|72% 14|14
AAR 38|45 23|18 82%|78% 9|8
8v8 30|36 27|20 75%|71% 16|16
Valley 33|42 27|19 80|78 14|12

Su27 instant action
Intercept 34|44 26|19 83%|80% 10|10

Ka50 Instant action
Shooting range 37|41 23|20 84%|81% 9|10

Viggen instant action
Offensive counter air 31|42 29|19 85%|78% 10|10

Su25T instant action
Free flight 36|45 25|18 88%|81% 10|9

Mig21 instant action
Free flight 28|36 29|21 77%|71% 18|20

PG

FPS, GPU frame time(ms), GPU usage(%), CPU frame time(ms)

F18 instant action
2v2 33|40 25|19 75%|73% 16|16
AGM65 33|43 26|17 80%|75% 11|11
Ready Ramp 26|32 30|24 75%|69% 22|22
AAR 30|42 28|18 83%|78% 11|10

Su-27 instant action
Intercept 37|43 26|19 84%|80% 7|9

Ka50 instant action
Firing range 31|35 28|22 82%|82% 13|15

Viggen
Beach party rockets 27|36 32|22 80%|77% 13|15

Su25T
Strike 33|40 25|19 80%|75% 14|14

Overall the 2080ti yields exactly 25% uplift in fps and similar decrease in frametimes. FpsVR is a great utility and gives you a visual representation of your frametimes as well as the raw numbers above. Basically the GPU frametimes are almost always in red (bad) whereas the CPU frametimes are always green/amber (good/mediocre). Clearly the 5k+ on my rig and at those settings is GPU limited. BUT the utilisation is still only about 75-85%. DCS really needs more VR optimisation.

Wags, Please!?

Similar numbers are seen in MP. With the 2080ti on the 104thand BF I get 36-45fps fairly consistently. If you’d have asked me before I’d have said that was unplayable low but I find it actually quite playable.

For reference in the above missions with Pitool 1.0, SteamVR 60% and the same DCS settings I get almost 60 fps. I need to spend far more time experimenting and tweaking the options to find what works best for me. I really wish it was better documented how the pitool, SteamVR and DCS PD setting all interplay with one another. There are too many combinations to test all of them and most of us will have different preferences. As such the numbers ive posted above should not be taken as absolute fps figures since it can vary so widely (30-60fps) with the settings you select, even between software updates. Ive tried to convey what the HMD is capable of and what the FPS cost is for someone more inclined to better visuals.

I tried the VR mod briefly but couldn’t get it to work. Im also not too keen to mod my game much and had heard it needed further modding to make it IC compliant. Furthermore it may require further tinkering to make it compatible with the 5K+. If anyone has the expertise to make it work for me im happy to give it a go. Any extra fps id get id put into turning on MSAA!

Verdict
Overall im impressed with what im seeing with the 5K+. VR is a very subjective experience. For me the 3D effect is pretty cool (AAR from an Il78 was the closest I felt to a wow moment) but Im not willing to forgo all visual eye candy and sharpness for it. I think the 5K+ is probably the minimum that I would accept to make the jump. As I said before Ive set the bar pretty high. For anyone currently using any of the current generation HMDs im sure youll find the pimax a big upgrade. You will need a monster computer though.

For me, im gonna keep using it for a few more weeks before I totally commit. VR kinda grows on you and I am excited each time I get to fly with it. If we could get the VR optimisations that would enable me to turn up the settings and crank up the MSAA I would absolutely consider myself a VR convert. Even in its current compromised state, im fairly sure ive already made the jump.

38 Likes

I posted it on DCS forums but figured folks here might be interested too.

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Awesome Review! :beers::sunglasses::+1::sparkles:

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Love your approach. I’m also in it for the image quality and will even sacrifice fps to get it.

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Very good review. Thanks.

The rift was enough to convert me to vr for dcs. Although the hit to visual quality was massive, the ability to look around naturally in my cockpit combined with the 3d effect was what I had been waiting for my whole life. And I began my gaming hobby on much worse graphics than this.

A visual upgrade will be much appreciated. The fps still worries me. I don’t like flying below 45fps and that is with asw on the rift.

Unfortunately MSAA is a massive hit in vr, in dcs. It always becomes a trade off between good fps or getting rid of the jaggies and shimmers. I’ve always had to trade away my MSAA to get the frames on my 1080Ti. We definitely need more vr optimisation in dcs.

Thanks again for such a detailed review in the context of my favourite sim.

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Awesome review and analysis, great to hear u posted it in DCS forums, they need to hear this and understand the potential of “real” VR :slight_smile:

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Yeah was just about to say, can you link your review in the DCS forum? I wanna read others’ reactions

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Sure.

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I envy you for beeing able to play any game between 30-45 fps even considerd without ASW.
I already throw up when hitting 30 fps in a 2D game. So that way you indeed may have enough performance head room to make the picture look even more beautiful. Glad you enjoy the device, have fun!!!, and thx for sharing your thoughts.

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I am also among those who would sacrifice FPS for visual treat. 30 fps is actually acceptable for me if there is no stutters. I hate stutters more than low FPS.

Also I feel low FPS is smoother on Pimax than on other headsets, but I am entering very subjective realm here.

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In regards to the sweet spot:

By contrast the 5k+ you just put it on and most of your vision is perfectly clear and in focus.

Interesting, I heard from some people that it took them 30 min to get everything perfect. I wonder if either it was easier for you, or the quality could be even better if you spent the time to adjust the IPD and get the positioning right.

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Maybe I am assuming too much here but I am sure he meant AFTER he of course set it up regarding IPD and strap setting …etc. Not just got his delivery, opened the box and immediately all was perfect for him. Unless the default IPD and straps just happen to be his requirements. Once you got it dialed in initially, you should be able to just put it on at will and be good to go. That is how it is for all my headsets.

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Nice review well done… i noticed that you have Vsync enabled in your settings, i actually think you can remove it as you don’t really need Vsync in VR as its really for screen tearing on monitors. that might gain you some additional FPS.

Eno

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I dunno. Maybe we should wait until we can hear it from the horse’s mouth, but phrases like:

I think this explains why I had no nausea with the 5k+ despite jumping in to the 104th almost immediately.

convince me otherwise. (This sentence doesn’t sound like they spent 30 minutes doing setup)

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Cmon man. Of course I spent some time adjusting the straps and making sure the fitment was comfortable, IPD was dialed in and the position on my face gave me the best FOV and sharpness. It doesnt take 30 mins though.

My point was the sweetspot is large and easy to find every time you don the HMD,unlike the SO.

Sebastian (MRTV) said the same in one of his videos.

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Hi, very nice review.
As a backer 68xx i just have to wait lol, but i m a big fan of dcs world too.
Thanks for your tests and happy flying
See ya in the air :wink:

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Really nice review thank you and looking forward to fly with 5k+.
I found that post few month ago about shaders mod for DCS in Vr and i did get some FPS back.
You could give it a try :slight_smile:

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I experience the same as well.
Glad someone noticed this as well, I thought I was the only one and I am out of my mind

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@Rage as you geting low fps I am recommending you Shaders mod for DCS :

The changes done include:

  • Simplified canopy glass shader*
  • “Emulation” for the OpenVR hidden area mesh (not rendering area which you cannot see)**
  • MSAA is applied only on the middle area of view in VR***
  • Disabled histogram calculation
  • Disabled bloom
  • Simple tonemapping (doesn’t do much of anything, you may need to adjust gamma more often)
  • Disabled blur compute shaders
  • Removed resolveDepth shaders
  • Removed some refractions shader (not sure what it did)
  • Simplified grass rendering
  • Disabled atmosphere for things close to camera
  • Removed one GBuffer entirely for bandwidth savings (AO and emissivity are packed in same channel, cannot exist together)
  • Slight mip bias adjustment for text rendering (sharper text)
  • Reduced shadow PCF maximum sample count from 32 to 10
  • Disabled color grading
  • Sun flare hidden (it no longer worked right, possibly due to removal of resolveDepth)
  • This optimization does not work with planes which do not use the glass shader for the canopy glass. For example the A10C and Hawk. It works at least with the Hornet, Harrier and Viggen.
    ** If you see an area around your peripheral vision rendered incorrectly open Bazar\shaders\deferred_HMD.hlsl and increase the MASKSIZE value. The default is optimized for HTC Vive.
    *** You can also adjust MSAA_MASKSIZE value from above file, which is the size of the area onto which MSAA is applied when it is enabled. Default is a very small area in the middle of the view.

Some of these are quite visible changes like removal of tonemapping & bloom, simplification of the canopy shader and shadows, and likely many features like DOF or SSAO no longer work. I would expect there to be other broken features too, I haven’t played with it that much yet.

The performance gain however is pretty good, it can be up to 50% or more in conditions where the GPU is the limiting factor.

Example scenes:
Stock shaders in Hornet, 65fps: http://junk.kegetys.fi/xzy/carrierlanding_orig_ssaa.jpg
With the mod, 98fps: http://junk.kegetys.fi/xzy/carrierlanding_opt_ssaa.jpg
Stock shaders in Harrier, 61fps: http://junk.kegetys.fi/xzy/readyramp_orig_ssaa.jpg
With the mod, 94fps: http://junk.kegetys.fi/xzy/readyramp_opt_ssaa.jpg
(These are taken in non-vr mode with some SSAA to get accurate FPS numbers)

Download for DCS World 2.5.4.25729 : http://junk.kegetys.fi/DCS%20VR%20Sh…5.4.25729.zip (latest)

Download for DCS World 2.5.3.21107 : http://junk.kegetys.fi/DCS%20VR%20Sh…5.3.21107.zip (old version)
Download for DCS World 2.5.2.19273.411 : http://junk.kegetys.fi/DCS%20VR%20Sh…273.411(b).zip (old version)

See the readme for install instructions. Its very likely it will break with future DCS versions that change the shaders…

It works in non-VR mode too, but likely the performance gain is not that huge unless you play in very high resolution.

Settings I use: http://junk.kegetys.fi/xzy/vr_settings.jpg

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Geez, congrats if you feel 30-40 fps is playable. For me, anything below 90 fps feels very different and ruins my immersion, as it destroys the feeling of being in flight, sailing across the sky.

Btw, you’re completely wrong about the GPU bottleneck in DCS. The CPU frametimes (basically anything above 7ms) make it totally impossible for the GPU to finish under 11ms. Sure a 2080Ti will complete the frame sooner but won’t be able to hit 11ms. It’s like giving a handicap of 10 laps in a Formula 1 race - a faster driver MIGHT catch up to the leaders but the only real difference is whether they will finish 6th or 13th.

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