I see everyone using the NG locks their framerates at 20... even on supercomputers like P2.8s... I only have a 1.5, yet still have bursting frame rates of 30 in the 2D panel... with fluctuations down to 12.. on my Radeon 9700 PRO. Locking at 20, it still looks jerky to me and I still so no advantage whatsoever.Can someone convince me that I too should lock my framerates? As I have used FS9 through beta testing etc... I was floored MS wanted us to always lock it, seems like an excuse for less than fluid FR - not like the smooth ones we used to get in 2002. I have tried it all over and over... and still think leaving it unlimted is better.. yet, please tell me as a new NG customer now, maybe I should...especially for lower powered computers like mine.Thanks!Peter

Well...the human eye can see 20-24fps,so whats the need to set the fps higher than you can see?? I think TV is around 25fps,and nobody complains about stutters there :)So there is absolutely no point in setting your fps higher than 18-25.Johnny"I'LL BE BACK"[div align=center]http://www.avsim.com/hangar/fly/josve/zone.jpg ][/div

That is not entirely correct.Someone else posted an interesting topic on this issue ('m not sure where though). Basically, a human eye can not see more than 24 fps if the transition between the images is very smooth. No flight simulator can provide that smoothness that at 24 fps you can say that you wouldn't notice say 30 fps. From personal experience, I can tell you that I do notice 24 fps, and that for my personal taste an ideal FPS would be around 30 to 35.TV's do run at 25 fps, but remember, here the image-transition is very smooth.Regards,Mark

>TV's do run at 25 fps, but remember, here the image-transition>is very smooth.>Regards,>>MarkIn the US, TV runs at 29.97 frames per second, and film runs at 24.I find that 20 is acceptable, and that more is "wasted" on me.

Hi Peter,Basically, there is no need to keep your framerates locked if you prefer that. Computer systems as well as flightsim setups (extra scenery, traffic, weather programs) etc. are unique to each of us and the best thing to do is to experiment for yourself.Personally, I prefer to keep FS locked at 20 or 18 (PIV 2.6 @ 3.1, Radeon 9700 Pro) just to avoid the wild fluctuations you do get in FS2004. The difference between framelimited top rate and bottom rate is smaller, so at least that makes it feel a bit smoother.With FS2002, after many complaints about stutters in FS2000, Microsoft decided to give smooth framerates priority, resulting in scenery textures going blurry and autogen dropping out instead if the system could not keep up-and there always were complaints about blurry textures in FS2002.With FS2004, they appear to have chosen a system where the integrity of the image takes precedence over smoothness again-so in complex situations, the system will take it's time to draw the complete image as best as possible, resulting in stutters. Any current system goes down to 12 fps or even lower, when you come near a busy airport with lots of traffic, clouds and ATC communications going-and graphics sliders to the right.So the best way is to experiment, and go with the kind of settings you are most comfortable with. There are plenty of tweaks and tips about on these forums, some do more than others, some are just snakeoil and many involve trade-offs in image quality and speed, but there is no magic bullet-not even in hardware (yet).Best,Martijn

Hi Peter,Well their are some reasons to keeping your fps locked at say 20 to 30 depending on computer specs or personal prefrance.This is because when the pc has loaded them 20 fps in your area it can load up the external auto gen scenery and other things in the background more quicker.If you set your fps to unlimited the pc will always waste its bandwidth giving you the most fps in cockpit etc, whilst if it is set to a number of say 10 20 30 40 whatever after this number of frames is loaded the cpu will load the auto gen clouds coming up in a new area ahead of you which has not yet been cached by the system and so will end up providing you with a more fluid motion.Their are some other posts up and around that explain this a bit better try the msfs forum as well. I just tried to offer some quick info for you.Regards, Mark

Consistency is far more important than how high the FPS are in a 3D app like FS that uses relatively slow moving scenes over a large depth of field. This is why it's better to lock your FPS at a level that the sim is always going to be able to achieve rather than to let it go wild fluctuating between extremes. The eye very easily detects those fluctuations and it makes the sim look choppy.What was said about the eye not being able to detect more than 24FPS is false based on everything I've ever read - the level is actually somewhere around 72. I can absolutely see a dip between 60 and 30FPS in a first person game for instance. 60+FPS is usually the target that a new high end video card is shooting for in most games. 72Hz is also the refresh rate on a monitor where flicker becomes imperceptible...Ryan

>Well...the human eye can see 20-24fps,so whats the need toThat is a wrong belief that has a very hard life. The human eye can see much more than that.>set the fps higher than you can see?? I think TV is around>25fps,and nobody complains about stutters there :)Have you ever heard about motion blur?When filmed at 24 fps, each image is exposed during 1/24s minus the time it takes to advance the film and close/open the shutter. During this time, the scenery does not freeze. So in effet, the camera does not capture a still image, but a moving one. What happens when the subject moves while you photograph it is that you get a blurred image.The human brain will not see each image as blurred, but will magically show you fluid motion. Actually, 24 fps is even to much. On a scenery moving at high speed (e.g. a formula 1 passing before you), 10 fps could also give you the impression that the movement is smooth (it would be twice as blurred though).In a computer game, each image is computed frozen and crisp. The number of fps you need to acheive smooth movement depends on the speed the scenery moves. Imagine an object moves 24 cms on the screen in one second. Each image would show it jump 1cm. That would clearly not be smooth.The fps number needed is equal to the number of pixels the scenery has moved in one second. In other word, if the scenery has moved 100 pixels in one second, you would really need 100 fps to see it perfectly smooth.>So there is absolutely no point in setting your fps higher>than 18-25.To fly jetliners, I agree there is no need to more than 25, but this is because the scenery moves slowly. On the other hand, 25 fps is definitly not enough to correctly handle some aerobatics using the Extra 300.Eric.

I just wanted to add that it also depends on the eye that is in question.Some people don't see TV flicker (in Europe 50 Hz) while others (like myself) can even see 85 Hz.Regards,Mark

Hi Peter,I used to run FS2002 on an Athlon 1GHz computer, and locking or unlocking frame rates made absolutely no difference in performance. However, now I'm running FS9 on an XP3000+ with 1GB rAM and a Radeon 9700 Pro, and locking fps makes all the difference. For example, if I fly at FL 370 over the Atlantic, unlocked fps can easily peak at numbers well in excess of 100. However, when I turn or clouds build up, the fps can drop quite a lot to around 40 or so. Now that's quite a big drop and will result in some stutters, so locking it at 30 will give a much smoother performance. So, from my observation, it is not the actual fps numbers that determine smoothness, but the magnitude of the percentage change in frames - e.g. a drop from 200fps to 100fps will give you just as much stutters, as a drop from 20fps to 10fps. The reason why I never saw this phenomenon on my old 1GHz computer was because the CPU was pushed to the limit anyway, and therefore incapable of producing such large changes.Cheers,Gosta.http://www.hifisim.com/images/as2betateam.jpg

There is no magic number. It's different for every person. 72 may be "average", but I don't know.I know for sure that it varies from one person to the next. I've always been much more sensitive to refresh rate flicker than others. I remember one instance in particular where the flicker on a screen was annoying me to the point that I could no longer use the monitor without getting headaches, yet a co-worker couldn't see any flicker at all, on the same machine.I for one keep my frame rate unlimited on an athlon 3200 with 1024 RAM and a Radeon 9800 Pro, and I get around 20-30 in busy areas and 60-100 at altitude with few clouds, but after reading this thread I may try locking it around 30 or so, in order to keep the drastic framerate fluctuations to a minimum.

Eric, your comment about the motion in filmed graphics is spot on. However, your calculation with pixels moved to fps is absolute nonsense. According to your calculations, a plane doing a flyby in half a second from the left side of my screen to the right would require 2560 fps for me to see smoothly?I do agree that smooth fps are a requirement for good flight simulation. We're not in this for the eye candy, we're here for the simulation of flight.The interesting thing, while having logged over 200 hours in full-flight simulators, is that the detail of the graphics is certainly not as good as the graphics in FS2004, by any means. But, there are no stutters in the scenery, ever. And that is absolutely vital.Because the graphics are projected by three large projectors on all modern 180 degree field of vision simulators, the crispness of the imagery is not that important. If you look really closely, the edges of the runway, taxiway signs etc. are a bit soft. This aids termendously in your perception of smooth motion. Whether this is done by active anti-aliasing (I think not) or just natural and intended blurring because of the way the focus/distance from the projector to the screen (probably), I'm not sure.

Like Mark said above, another reason besides preventing fluctuations is in relieving the processor to do other tasks. If you are in a situation like you mention where your processor is capable of producing 60-100 fps but you are limiting it to 30 then you wind up with quite a bit of processor time left over to do other things like preloading textures, updating gauges, etc. That's the theory anyway.If you do try locking your frame rates please post here to let us know what your impression was. Sometimes no matter how good the theory is ones perception may be different when it is actually put into practice. ;)Don

>However, your calculation with pixels moved to fps is absolute>nonsense. According to your calculations, a plane doing a>flyby in half a second from the left side of my screen to the>right would require 2560 fps for me to see smoothly?Assuming you are capable to distinctly see these 2560 frames in 1/2 second, yes. Anything lower would result in perceived stutter.Do this test : Set autogen to max and lock fps to 15 or 18. Fly 150 ft AGL 250 knots and look at the builings on the left view. You can clearly see the buildings jump, their motion is not smooth. Now, change plane, slow down to the slowest you can (50 kts) and look again at the buildings : the motion is now nearly smooth. It's the same buildings and the same fps. Can you see my point now?In practice, it's not possible to display more fps than the monitor refresh rate anyway (let's say 100). And even this number is still above what the eye can distinguish. If an object was passing through the screen in 1/2 second, it's motion could only be described using 50 frames. If the screen is 1600 pixels wide, each image would jump 32 pixels. You call that smooth?Eric.

That flicker has a lot more to do with phosphor persistence than anything else. Do motion pictures flicker for you? TV?Lee Hetherington (KBED)