I've been playing with cl_independant phys to get a few more fps outta qw and I got to thinking "how many frames per second can the human eye take in?"

After reading for a bit I found this quote:

"So what is the answer to how many frames per second should we be looking for? Anything over 60 fps is adequate, 72 fps is maximal (anything over that would be overkill). Framerates cannot drop though from that 72 fps, or we will start to see a degradation in the smoothness of the game"

URL:
http://www.daniele.ch/school/30vs60/30vs60_3.html

id made quake to run at 72fps, is this the reason why?

Seems like nonsense, anyone can see the difference between 72 and say 100 fps with their own eyes.

I cant see the smoothness I just feel it

yea, well doesn't the eye only see like 24 fps? anything higher will be seen as a "rolling" figure
the human eye sucks :/

I think there has been some tests where the human eye have indentified an aircraft that was visible for 1/180 seconds.

This is the favorite topic for many CS players. "I need 100 fps, I can spot the difference between 100 and 98 fps!!!"

There are two parts to this problem. The first one is fps related while the other one is directly related to the monitor's refresh rate.

How the eye reacts to different FPS:
The human eye does NOT have a fix "refresh rate" but rather sort of a constant flow of information. While a high FPS will be considered by many to be "smooth", the lower limit of when it becomes unsmooth may vary. Some people can't "feel" the difference between 60 and 77 fps, and yet other people consider 30 FPS to be completely adequate. Note that the FPS is only a measurement of how often the information on the screen changes, not how long it is displayed. Therefore, a low FPS will be noticed because of how it "feels", rather than because of how the eye percepts it. I, myself, would prefer to play with 200 fps since it's a much smoother ride for me. But since I'm using fuhquake that's not an option. :|

How the eye reacts to different refresh rates:
As previously stated the human eye does not have a fix refresh rate. It is capable, however, of detecting the minute pauses between each cycle of the beam in a CRT display. Meaning, if a CRT has a refresh rate that is too low (the rate at which people notice the "jitter effect" differs, but for most people lies around 75 Hz), the eye will spot the pauses between rendering passes by the electron beam (I presume all of you understand the principles of CRT monitors), thus causing the jitter effect that is most noticable on bright areas. This effect does NOT appear on LCD/TFT monitors, since they are constantly lit from behind.

Oh, and by the way - why not start a thread about Intel vs. AMD?

Stupid article. He gives this science babble as if he knows what he's talking about, but then bases his conclusion on nothing more than personal experience.

Yeh I'd have to agree kalma even tho I posted it, read a few articles but they all seem to be from gamers not scientific proof, I'm still in the dark as far as the human eye goes. ui's explanation seems more truthful, is there a limit to fps?

What the hell 77fps does me fine, I'd love to see qw running at 154fps but ma monitor just no up to the task

its not only for cs players, I complain aswell when my fps goes down to 75 from 77!!
it feels so strange......

I have played QW on 2 diff pc's alot and I get fps dropps all the time on both machines, why?

1, Ahtlon XP 2000+ (1.68ghz) 256 ram GeForce ti-4200 (win2k)
2, Athlon 1ghz 756 ram Radeon 9700 (win2k and winxp)

With both pc's I got QW running smooth when turning off winamp and mirc when playing qw (so goes for firewall/antivirus and all the other programs were always shut down while playing qw)

but as I remember it on my p2-300mhz 192 ram Voodoo 2 I could get stable 77 fps all the time and run winamp at the same time!

now thats strange!!

If your Hz is 77 and fps 75 (vsync off), you get awful tearing. That's a different issue.

Write something better yourself then. I'd like to see you try and explain this phenomena without getting anywhere near your own experience in the matter.


Your monitor has nothing to do with your FPS unless you're using vsync.

And for those of you who didn't recognise it, the part about CS players was irony.

Nothing wrong with writing about his own experience, just stupid to try to back it up with science babble that does nothing to prove his claim: "Anything over 60 fps is adequate, 72 fps is maximal (anything over that would be overkill)."

I believe its a conditioning. Most NTSC tv screens in America run at 640x400 at 60hz so ever since we were hatched and put in front of a tv screen
we've been trained to see 60fps. Even when we started playing quake 60fps(max), now though since some clients lift cl_maxfps to max ability of monitor refresh, we notice, "hey WTF this is better!" Well, for NQ we dont get ANY physics advantage from more fps, infact once u get >500 for (broadband atleast) you begin to lag!
Whats the FPS of realtime realworld?! Unless your drunk, I'd say its everything/second!

""National Television Standards Committee". The television standard for the US, administered by the Federal Communication Committee (FCC). The number of scanning lines in the luminance signal (Y) is set at 525, and the field frequency is 60 Hz. 30 frames are transmitted per second. Set in 1953."
Only 30 fps anyway.. PAL has a bit higher resolution but at 25 fps (NTSC uses 525 lines per frame (as opposed to 625 with PAL))

You can't compare to TV anyway because in TV the picture is updated line by line which makes it look smoother at lower refresh rates. This really isn't that hard to test, you need two computers with qw and then ask your friend to put say 72fps/72hz setup on one of them and 100fps/100hz to the other and then you try to tell which is which. My bet is that anyone can tell the difference.

blAze: line by line? as in progressive updating? thats hardly the case for all televisions though the older interlacing is being phased out, theres still a long way to go til that.

Correct. I didn't try to prove his claims because I don't agree with them. I can easily spot (or rather, feel) the difference between 60 and 72 fps, especially during tight turns and other sudden motion. I was merely sorting out the two aspects of the problem, I didn't try to give a solution or anything.

BlAze is correct.

Whether a certain number of frames per second appears choppy or not depends almost entirely on conditioning. If you saw 30 fps on a computer for a very long time, then moved up to 60 fps, you would think it was much smoother. However to a person used to 77 fps, 60 will appear choppy. There might not be an end to this..., it might be true that one could tell the difference between 900 fps and 500 fps if they were conditioned properly, however i've got nothing that refreshes that fast to know for certain.
Television is a completely different story, even though it runs at 25 fps on average it has "motion blur", so it doesn't appear choppy at all. I think some game companies have toyed with the idea of creating motion blur for their computer games, but for whatever reason their attempts have been unsuccessful.

I have a theory about what makes it so easy to spot drops in fps is that the (i.e.) 77 frames aren't drawn evenly spread over the second. 77->75 as Sassa mentioned.

Such as: 70 frames are drawn in 500ms and the remaining 5 are drawn each hundred ms until the 77 frames have been drawn in that second. Those remaining 5 frames would feel like 20 fps. Extreme case.

Don't know if this changes depending on the setting of vsync, but a long time ago I played qw with my Voodoo Banshee at 60hz with vsync on. And that felt MUCH smoother than 72fps with vsync off @ 60hz. Might have something to do with it. Different games probably use different techniques handling vsync.

Games which doesn't seem to be running smooth are a pain in the ass anyway...

Heh, you could have quoted me instead of posting as me : )

Anyhow I use ezquake 800x600 w/cl_maxfps 154 and 154 hz set with powerstrip on a crt monitor and I like it very much.

I wish I could do 1024x768 at maxfps/hz 154 but my monitor won't do it. Same with 1280x960. In fact if I could run 1600x1200 at maxfps/hz 154 i'd do that. 800x600 at 231 fps/hz or 308 fps/hz would be interesting as well. I'm sure someone has a monitor (crt) that can do 250 hz at 640x480 and/or 800x600 and could try 231 fps. That would give you 3 frames for every server frame rendered, and it should be jolly good.

I would be interesting in hearing about anyone who could do that on their monitor because i'm considering buying a new system in the near future and i'm going to have to be getting a CRT monitor b/c lcd's still suck for games imo. So it would be nice to know what model CRT is pulling 250 hz + at 800x600 or better.

I cant find it now but I have seen a test where pilots could see a "target" which was visible for 1/200 seconds. But as has been previously mentioned its probably the unsmoothness we feel not the absolute fps.

well I can tell You from my experience. on March 2005 I switched to EZQ, and started to play on indep. phys, maxfps 0, 150Hz @ 800x600, physfps 77 and stuff like that. I dont have to tell You how smooth that is, and for me it was even more smooth, because before march 2005 i was plying on mqwcl, 77fps, 75Hz (sic!). right now, i moved to 20" LCD Widescreen, running 1152x864, 75Hz and maxfps 0. it took me over week to get used to 75Hz......right now i "feel" the smoothness, but its not the same as for 150Hz in CRT.

Actually no, the method is always the same. One frame is displayed during one screen refresh. Differences can be felt when people are using double/triple buffering (latter increases input lag even on CRTs at low fps situations) and when the fps/screen refreshrate is lower/higher (ie. 75Hz 75fps has more "lag" than 150Hz 150fps, especially when considering input lag).


There is none, or if there is they are really rare and probably cost too much.

One of the best monitors with really high refreshrates is Viewsonic's P227f 21" that can do 100Hz @ 1600*1200 or 150Hz at 1024*768 but it's maximum vertical refreshrate is still limited to 160Hz. It's all about bandwidth, the highest performing CRTs are only capable of 360MHz in the terms of video input bandwidth. Besides, there isn't much room for improvement either due to fact that current gfx card ramdacs are running at 400MHz.

CRT is almost dead, look at stocks. LCD/TFT/WHATEVER sux. Hope my'n CRT monitor die after there appear worth it replacement.

You will be able to buy second-hand CRT then.

Just to diss LCD some more: http://en.wikipedia.org/wiki/Input_lag Check out the external links.
Note that this is yet another form of latency on top of the response time and refresh rate issues. Not all LCD suffer from this, though.

There actually might be some hope yet though Renzo. I'm using a rather old 19" iiyama visionmaster 450 (not pro) that I purchased in 1999. 154 hz is past its specifications at 800x600, so maybe i'm shortening the life of my monitor or what have you, but it's working, and I can see the difference between 120/144/154.

So it's very possible that that viewsonic monitor you mentioned is capable of the refresh rates I need, but the specifications give more "reasonable" max values. Sort of like overclocking one's cpu, it's never recommended by any cpu manufacturer, but that doesn't stop people from doing it.

I bought a Samsung SyncMaster 757MB CRT monitor 2 months ago and I couldn't be happier

The manual lists recommended values (rocommended resolution/refreshrate is 1600x1200@99Hz) and after installing monitor's inf the recommended max values can be accessed (pnp monitor inf allows only 85Hz refreshrate as you know). Specs are:

Resolutions up to: 2048*1536
Frequency:Fh: 30~130kHz, Fv: 50~160Hz

1024*768: 150Hz
1280*960: 120Hz
1600*1200: 100Hz
1920*1440: 85Hz
2048*1536: 75Hz

One shouldn't worry too much about shortening the lives of their monitor. Usually monitor can break down when frequencies exceed their limits. However this has been impossible quite a long time. When the signal is out of range, electron gun will be turned off. You can try to stress electronics by finetuning the absolute maximum refreshrates (depending on the resolution we are talking about horizonal frequency, that is the more important factor on determining max vertical frequency (within the limit of vertical range of course)). Running 130kHz scan rate on monitor capable of running only 130kHz could be shortening the life of the monitor.

(Overclocking a cpu and driving monitor at high refreshrates can't be compared, they are too technically too different things. Besides killing a cpu with overclocking requires high enough voltage with the combination of high temperatures. Running 2,4GHz processor at 3GHz within the manufacturers recommended voltage and keeping the cpu cool enough won't kill the cpu in 10-15 years or more.)

siikah, frames are drawn with a frametime so they are rendered 'evenly' across a second