For smoothness you need to be focussing on FrameTime - the time between each displayed frame remaining consistent.  Great post by @Noel a while back, but I haven't the time to search for it right now. Calling @Noel 🙂

 

FPS in flightsim is like 0-60mph times in cars. It’ll always be there. 
 

As a side note, 24 or 30fps when watching sports is awful. Same when flight simming if using trackIR or equivalent. The fast motion kills it.
Now if you just had a static view, it probably isn’t so bad. 
 

However, the goal for the future should be 120 FPS at 120hz. Anything beyond that is just diminished returns. 

Edited February 13, 20251 yr by Ianrivaldosmith

4 hours ago, Ron Attwood said:

People, and they won't be posting on here, will still swear blind they can see the difference between 100fps and 110fps. Leave 'em to it mate.

No kidding ... surprised said "people" haven't posted yet about how they believe 120 FPS is not enough and 240 FPS minimum and 1000 FPS is better.  

Even if one claims they can decern a difference from 75FP to 240 FPS, human reaction time is 100-120ms for the elite folks that "train" for quick reactions ... this includes fighter pilots, racing drivers/riders, athletes, and "professional" gamers.  For the average human and old folk it's 200-250 ms ... even higher if you drink and fly 😉

30 FPS = one frame rendered every 33.3 ms

60 FPS = one frame rendered every 16.6 ms

120 FPS = one frame rendered every 8.2 ms

240 FPS = one frame rendered every 4.1 ms

So as you can see, even the best of the best human race reactions (100ms) when they see one frame render at 30 FPS, 3 additional frames would have been rendered before super human can provide input.

At 60 FPS, 6 additional frames render before super human can provide input.

At 120 FPS, 12 additional frames render before super human can provide input.

FPS hunt is a wallet empty game ... what you want to be looking for is consistency if frame generation.  If you can hit 33.3ms exactly on every frame displayed, it will look smooth.  If you can hit 16.6ms exactly on every frame displayed it will look smooth ... etc.  What the eye detects that triggers annoyance is VARIANCE in the rendering of frames which is why Vsync is better than FreeSync and GSync.

So long as your PC can maintain (in all scenarios) a frame render frequency that matches you monitor's refresh rate (30FPS/30Hz, 60FPS/60Hz), it will be smooth.

Of course, heavy drinking can certainly improve the graphics quality 😉 and for less than a $5000 GPU.

Edited February 14, 20251 yr by CO2Neutral

14 minutes ago, Ianrivaldosmith said:

The fast motion kills it.

Sure, and restriction on 1 meter terrain resolution ... but when you swivel your head in a fast motion, are you actually recognizing (as in what is in each frame) the frames being render during motion or not until your head stops?

2 hours ago, JonathanC said:

Older eyes notice things less. The younger you are, the more you will notice the difference between 45 fps and 75 fps (for example). 

I'm 72y/o and wholeheartedly agree with the general point and I would add context will play a big role as well in how one reacts to what one perceives looking at a screen of MSFS.  When I was 42y/o it was nearly wire frames and 20FPS!  As time moved on thru FSX then P3Dv4.x for me I was delighted to have a solid 30fps, never mind the frame time variance.  And in P3D w/ high end airliners we had to turn autogen to sparse and fly from pre-dusk to post-dawn when it didn't matter what scenery looked like!  And disable all that Orbx scenery I bought it was way too hard on my sys then which was decent for its day.

FF to late 2021, over a year since 2020 launch, I was so stoked with my old PC to discover how to achieve ultra smooth video secondary to very low frame time variance at a modest rate of 30 with all ultra settings, and up a bit higher w/ less complex planes.  I was so stoked because this was the best I'd ever experienced in any flight sim with this massive increase in level of detail and complexity.

New build happened in April 204 to the current system.  We immediately went from 30FPS to 45FPS.   After many months of this going back to 30FPS was very....unacceptable!  Ouch, how did I cope with that back then?  But even 30FPS in the right context (taxiing, panning very slowly, etc) with ultra low FTV isn't terrible by any stretch.  Then over time we began adding demanding addons including Self Loading Cargo, APLv2, GSX and BATC and that last one pushed me out of a solid native rate of 45 using TAA and PrimaryScaling of 150 into needing to depend on DLSS FG.  So now we're at DLSS4 + DLAA and the base rate has become 60FPS-fg.  I installed 2024 just 4 days ago and went back to TAA and native rendering for its superior IQ overall and the lightweight Longitude and with no ghosting/smearing in glass cockpits.  Goodness!  Wasn't quite as good as 60 now was it?   

Moral to the story:  be careful what you get used to if you can't maintain it where you need to!

 

It's always been that way. There are people that enjoy flying and people that stare at a FPS counter, obsess about performance, and tweak until the cows come home, even when everything is working great, because maybe it could look a little better. I wonder if some of them have ever flown a complete flight without worrying about what FPS they are getting or if the ground textures might look a little less sharp or whatever. They will argue scientific facts about what the human eye can see, apparently not having eyes of their own. I feel fortunate to have eyes with the natural ability to see when my flight is smooth without the need for help. I have turned on the counter before to check whether my frames were being limited to what I had set it. Probably looked at a FPS counter three times in the past 4 years. Even stranger I have a 3080 and there are people with 4090's counting frames.

Edited February 14, 20251 yr by desbean

I find 60 fps is just fine, and with a good set up, can be achieved in MSFS2020 / 2024 at 4k and mainly ultra settings.

I couldn't go back to 30fps now, which most simmers used to be happy with if you could achieve it in FSX / P3D etc.

My monitor only does 60Hz at 4k anyway, so no point me trying for more. 
It's all about consistency now for me, or frame times or whatever you call it.

I seem to be doing alright in 2024 apart from really busy international airports.
Even over New York on full detail in the Cessna 172, it seemed to be holding 60 alright in 2024.

I am still experimenting on what will add more consistency or smoothness, to give me a bit more headroom in 'busy' areas.

I have dropped vehicle traffic down to 10% from 100% and it still seems fairly realistic and I get less skips.
It still seems to zip about too quickly.  I wonder if they dropped the speed down to about half would that also help (it might look more realistic also).

I also have trees at medium, and once again it adds a teeny bit more smoothness, and once again can look more realistic, as lets face it, there are far too many in 2024 it seems.

I think the general consensus amongst simmers is once you hit 60 fps, the smoothness is the key thing, not going for 240 fps.
If you can hit 100 fps and keep the smoothness, then fine, but most would be out of that league I think.

3 hours ago, desbean said:

It's always been that way. There are people that enjoy flying and people that stare at a FPS counter, obsess about performance, and tweak until the cows come home, even when everything is working great, because maybe it could look a little better. I wonder if some of them have ever flown a complete flight without worrying about what FPS they are getting or if the ground textures might look a little less sharp or whatever. They will argue scientific facts about what the human eye can see, apparently not having eyes of their own. I feel fortunate to have eyes with the natural ability to see when my flight is smooth without the need for help. I have turned on the counter before to check whether my frames were being limited to what I had set it. Probably looked at a FPS counter three times in the past 4 years. Even stranger I have a 3080 and there are people with 4090's counting frames.

Excellent post. I agree 100%

I also think that simmers with average hardware seem less likely to worry about performance, fps, tweaking this, tweaking that, compared to folks who fell into the rabbit hole that Nvidia gladly dug for them and spent an arm and a leg on overpriced hardware. 

The funny thing that this post makes basically nothing else than replacing "FPS" with "smooth", which is in the end exactly the same thing but with "smooth" being a totally subjective "measure". While for someone rock solid 40 FPS is "smooth" enough, others find it still somehow borky and prefer 60FPS or even more. 

So why accusing those who prefer talking about numbers (FPS) instead of subjective meanings (smooth)? We all want the same in the end, that is a good experience with minimal stutters (smooth 😉 ). 

The OP is exactly right.  The reason I think people talk about fps is it becomes more of a status symbol around who has more.  To me, I have a sim that works smoothly, is visually incredible and functions the way I want it to almost 100% of the time.  My computer is not being over taxed- what else could I ask for?

14 minutes ago, jspilot said:

The reason I think people talk about fps is it becomes more of a status symbol around who has more.  To me, I have a sim that works smoothly, is visually incredible and functions the way I want it to almost 100% of the time.  My computer is not being over taxed- what else could I ask for?

As I wrote, your "my sim works smoothly" is exactly the same statement as "my sim runs at constant 70FPS", except your "smooth" is a less precise, more subjective measure. The meaning is the same, so why accusing those preferring numbers to use it as a "status symbol"? 

My framerates will be up and down like a roller coaster, because I do not limit them in any way at all. Neither do I "enhance" them with FG or anything else. Consequently, there are times when I notice a slight judder, but to be honest this is usually only when I am on the ground at a super detailed airport (and even in these cases, the judder tends to vanish at some point; maybe it is loading internal modelling?). Generally, performance is consistently impressive, even over extremely dense scenery areas like London....and I really do not care if this is 30/45/60/stupidlyhighTM fps.

After trying every option, I settled for just limiting frames to 30 fps in 2020 with AMD Chill for the smoothest experience without stutters, blurring, or artifacts. I mainly fly airliners with the usual add-ons that makes it difficult to find settings that work smoothly in every scenario. My CPU/GPU utilisation is about 50% so the PC is cool, quiet, and burning about 150 watts.

When I do fly GA, I let her rip and enjoy the big visual improvement of 60+ fps.

I was thinking of upgrading my CPU to a 9800X3D but the performance gain would be poor value for money as I'd have to switch to AM5. I'm going to wait until I can start using 2024 as performance might be better with the add-ons I use.

One thing people seem to forget here is latency. It's not a big issue in a slow-paced title such as a civilian flight simulator, but it has a big impact on faster games, especially when playing competitively.

And while the numbers in the post quoted below are correct, I'd debate the conclusions drawn:

12 hours ago, CO2Neutral said:

Even if one claims they can decern a difference from 75FP to 240 FPS, human reaction time is 100-120ms for the elite folks that "train" for quick reactions ... this includes fighter pilots, racing drivers/riders, athletes, and "professional" gamers.  For the average human and old folk it's 200-250 ms ... even higher if you drink and fly 😉

30 FPS = one frame rendered every 33.3 ms, 60 FPS = one frame rendered every 16.6 ms, 120 FPS = one frame rendered every 8.2 m, 240 FPS = one frame rendered every 4.1 ms

So as you can see, even the best of the best human race reactions (100ms) when they see one frame render at 30 FPS, 3 additional frames would have been rendered before super human can provide input.

At 60 FPS, 6 additional frames render before super human can provide input. At 120 FPS, 12 additional frames render before super human can provide input.

The point being that latency from mouse input to seeing the rendered image on screen is typically 3-5 frames, depending on the game engine, leading to latencies of 160ms for 30fps and 80ms for 60fps.

This is definitely something I can still feel as a "rubber band" effect when the image lags behind the mouse movement. So much so that I barely could use an old computer connected to a 4K monitor at only 30fps because the mouse movement felt so sluggish. At 60fps it feels ok to me (as an occasional gamer in my 40s my reaction time leaves much to be desired), and I certainly feel an improvement going from 60fps to 120fps, but I guess around 90 I enter the zone of diminishing returns.

Visual smoothness is something else, and independent of the input latency. I used to be ok with 30fps when I was a student and had to make do with old hardware, but now I'm glad when I can get more. In this regard, frame generation is amazing. However, keep in mind that frame generation doesn't help with latency, in fact it has a negative impact. It's kind of counteracted by Nvidias anti-lag features, but you can still turn these on without using FG.

Anyway, while the numbers can be measured precisely, the way we experience it is very subjective. I totally understand that some people prefer to turn up the visuals in MSFS and accept lower framerates, whereas other simmers aim for a stable 60fps. Still doesn't mean that measuring fps is useless, and that more than 60fps are for bragging rights only. 

To the OP:

What I don't understand is why people obsess over what someone else obsesses over.

Those who chase that extra FPS cause the games to improve for everyone.  If it were left to those self proclaimed "20 FPS is all you need" folk, then imagine the state of the game.  Nothing would be as efficient as we have now.

FPS seekers cause developers, GPU makers and the like to code better, develop better and move the gaming industry forward.  If it weren't for them, ya'lls precious 'study level' stuff would be a lot more cartoonish.

I thank those who push the game forward.