The purpose of setting a certain FPS lock is to ensure rendered frames are produced on screen in an even manner, this is commonly know as "frame time" , "frame pacing" etc. When frames are rendered erratically (out of time) it manifests itself as a stutter. 

In order to achieve even frame timings you can utilize the refresh rate of your monitor in conjunction with the vsync setting.

You will also need to make sure that your rig can produce consistent FPS above that of what you choose to lock it at. This inturn should produce smoothness. Due to the natural variations in simmers rig specs is why you also see discrepancies of the FPS that is considered "smooth" . 

 

If you don't get 60 FPS on a 60 Hz monitor you will have stutters even if your eye perceives 24 FPS as smooth... 

Anyone knows if FFS/FSTD has FPS (or Iteration rates) requirments?

I tried search on FAR.60 but it's too complicated to understand as simple FPS....

4 hours ago, Tomaz Drnovsek said:

If you don't get 60 FPS on a 60 Hz monitor you will have stutters even if your eye perceives 24 FPS as smooth... 

Depends on the brand and type and how the user sets everything up

There are more than enough monitors that can’t get below 60 hertz and with NVI set to 1/2 refresh rate can use Unlimited to see 30 FPS without any stutters.

3 minutes ago, GSalden said:

There are more than enough monitors that can’t get below 60 hertz and with NVI set to 1/2 refresh rate can use Unlimited to see 30 FPS without any stutters.

I'm yet to see any kind of proof of 1/2 refresh rate actually working in P3D v4. Everybody seem to know somebody who apparently won a jackpot and got a monitor that defies the fact that 1/2 refresh rate vsync only works in true fullscreen applications which P3D is definitely not. Even if that is actually a thing, it's true only for a just a few lucky ones. I used 1/2 rr in FSX and got a silky smooth experience so I'm very familiar with this setting. Sadly I, and nobody I know, wasn't able to get it to work in any P3D version since v2. And I tried. I tried a lot.

14 minutes ago, Tomaz Drnovsek said:

I'm yet to see any kind of proof of 1/2 refresh rate actually working in P3D v4. Everybody seem to know somebody who apparently won a jackpot and got a monitor that defies the fact that 1/2 refresh rate vsync only works in true fullscreen applications which P3D is definitely not. Even if that is actually a thing, it's true only for a just a few lucky ones. I used 1/2 rr in FSX and got a silky smooth experience so I'm very familiar with this setting. Sadly I, and nobody I know, wasn't able to get it to work in any P3D version since v2. And I tried. I tried a lot.

Rivatuner RTSS can handle half-refresh rate sync externally.  There are a number of discussions here about using RTSS and its scanline x/2 sync function to do this.  Also, see the link below

https://www.resetera.com/threads/guide-how-to-use-rtsss-scanline-sync-to-reduce-stuttering-screen-tearing-and-input-lag-on-pc-alternative-to-vsync-g-sync-and-freesync.138764/

5 minutes ago, w6kd said:

Rivatuner RTSS can handle half-refresh rate sync externally.  There are a number of discussions here about using RTSS and its scanline x/2 sync function to do this. 

I know, I tried it. Not even remotely the same result as 1/2 rr thing in NVI.

5 minutes ago, Tomaz Drnovsek said:

I know, I tried it. Not even remotely the same result as 1/2 rr thing in NVI.

I have it and it is working great. 4k monitor on 60hz, NVI at 1/2 refresh rate with TB ON. P3D V4.5 FPS locked at 33, FFTF with AGL 0-4000 range 0.01-0.20.

Steady FPS at 30, and smooth as silk.

3 minutes ago, ttbq1 said:

I have it and it is working great. 4k monitor on 60hz, NVI at 1/2 refresh rate with TB ON. P3D V4.5 FPS locked at 33, FFTF with AGL 0-4000 range 0.01-0.20.

Steady FPS at 30, and smooth as silk.

I'm jealous.

I don't have a lot to contribute to the "what fps is best" debate other than the fact that those who fly online should note that elapsed time in all ESP based sims is based on frame rate, and roughly speaking 29.9fps seems to be very close to real time.  If one flies online with others (say a VATSIM event) and all things are equal except fps between two systems,  you'll find that an aircraft at 60fps will out pace an aircraft flying on a system with 30fps.  The same of course is true for those with low fps.

Best wishes.

 

I recently moved to half refresh rate using rivatuner and have never been happier.  I had always read that consistency of frame rates is more important than the frame rates themselves and i was doubtful, but now I’m on-board with that concept.

1 hour ago, DaveCT2003 said:

I don't have a lot to contribute to the "what fps is best" debate other than the fact that those who fly online should note that elapsed time in all ESP based sims is based on frame rate, and roughly speaking 29.9fps seems to be very close to real time.  If one flies online with others (say a VATSIM event) and all things are equal except fps between two systems,  you'll find that an aircraft at 60fps will out pace an aircraft flying on a system with 30fps.  The same of course is true for those with low fps.

Best wishes.

 

That's interesting to know. Glad you added that Dave. I guess that's why 30 FPS seems to be such a highly recommended target.

9 minutes ago, Rob_Ainscough said:

(I have them all and those future ones I can't discuss)

LOL! Sometimes I just hate you!!😂

To perceive the sim as "smooth" depends on many things, not only framerate.

If you don't use any head tracking device (TrackIR or VR), then 30 fps will be good enough for some people, as long as the screen refresh is tied to the framerate, using Vsync or 1/2 rate Vsync.

I am a TrackIR user and as with VR, input lag becomes more important, and here is where the more frames you can get, the better the experience will be.

I find a minimum of 60fps (~16ms input lag) is required, but 90fps or above is needed to feel really connected.

That's why for VR, 90fps is considered a minimum to avoid naucea.

With G-SYNC I get a tear free image as long as the fps stays above 30 and below 144, but there will still always be the occational stutter caused by loading scenery etc.

6 hours ago, Tomaz Drnovsek said:

I'm yet to see any kind of proof of 1/2 refresh rate actually working in P3D v4.

Yes I've been able to get the NVI 1/2 monitor refresh rate vsync to function, however the result was pretty awful with many screen artifacts and wobbles.

fyi I was at the time running Win7 and had to disable Aero for the NVI option to work.

Enter Riva Tuner Statistics Server (RTSS) - this tool works very well at providing a 1/2 refresh rate vsync for those running 60 hz monitors.

Running a 1/2 vsync on a 60 Hz montor works well, so well most people should be able to bump up their GFX settings for a more immersive experience.

Infact I don't know why P3D doesn't offer this sort of function internally via the GUI. (I note on occasion I've been able to glitch P3D into running as a 30Hz vsync on a 60 Hz screen so it seems possible LM could achieve such a config option).

Here's a link to a vid, you'll see a fps counter in the bottom RH corner and when it locks at 30 RTSS is working its magic 1/2 vsync operation. The vid includes the P3D GUI settings, and also shows the load being applied to the CPU and GFX card (at around the 4:45 mark).

Riva Tuner Statistics Server vsyncing @ half monitor 60hz for 30 fps @ L35 Big Bear airport

Cheers